Investigating Seafloors and Oceans: From Mud Volcanoes to Giant Squid

By Antony Joseph

Investigating Seafloors and Oceans: From Mud Volcanoes to Giant Squid offers a bottom-to-top tour of the world’s oceans, exposing the secrets hidden therein from a variety of scientific perspectives. Opening with a discussion of the earth’s formation, hot spots, ridges, plate tectonics, submarine trenches, and cold seeps, the text goes on to address such topics as the role of oceans in the origin of life, tidal bore, thermal effects, ecosystem services, marine creatures, and nutraceutical and pharmaceutical resources.

This unique reference provides insight into a wide array of questions that researchers continue to ask about the vast study of oceans and the seafloor. It is a one-of-a-kind examination of oceans that offers important perspectives for researchers, practitioners, and academics in all marine-related fields.

• Includes chapters addressing various scientific disciplines, offering the opportunity for readers to gain insights on diverse topics in the study of oceans
• Provides scientific discussion on thermo-tolerant microbial life in sub-seafloor hot sediments and vent fields, as well as the origin of life debates and the puzzles revolving around how life originated
• Includes detailed information on the origin of dreaded episodes, such as volcanic eruptions, earthquakes, tsunamis, internal waves and tidal bores
• Contains information on the contribution of the oceans in terms of providing useful nutraceutical and pharmaceutical products

• Language: English
• Publisher: Elsevier Science
• Release date: Dec 8, 2016
• ISBN: 9780128093634

Antony Joseph

Dr Antony Joseph has over 40 years’ experience in oceanography research on various aspects related to oceanographic sciences, ocean technologies, limnology, hydrology, meteorology, and surface meteorology technologies. He is currently retired but was Chief Scientist of the National Institute of Oceanography, India for 34 years where he conducted research in the areas of ocean currents, sea-level, and surface meteorological measurements. Dr Joseph has worked in numerous countries such as the UK, Norway, Portugal, France, Ghana, Singapore, Japan, South Africa, Russia, Australia, and USA on official capacity in connection with sea-level related research and operational activities. He has authored three Elsevier books: Tsunamis: Detection, Monitoring, and Early-Warning Technologies (2011); Measuring Ocean Currents: Tools, Technologies, and Data (2013); and Investigating Seafloors and Oceans: From Mud Volcanoes to Giant Squid (2016).

Book preview

Investigating Seafloors and Oceans

From Mud Volcanoes to Giant Squid

First Edition

Dr. Antony Joseph

Formerly, Chief Scientist, Marine Instrumentation Division, CSIR— National Institute of Oceanography, Dona Paula, Goa – 403 004, India

Table of Contents

Cover image

Title page

Copyright

Dedication

Foreword

Preface

Acknowledgments

Chapter 1: The Chaotic and Vibrant Seafloor

Abstract

1.1 Introduction

1.2 Discovery of Formation of Different Continents from One Big Land Mass

1.3 Evolving the Notion of Tectonic Plates Floating on Molten Lava

1.4 Triple Junctions on Seafloors

1.5 Rotating Microplates

1.6 Formation of Submarine Mountain Chains, Seamounts, Island Arcs, Mud Volcanoes, Canyons, and Trenches

Chapter 2: Secrets of Bermuda Triangle and Formation of Polymetallic Nodules

Abstract

2.1 Introduction

2.2 Riddle of the Bermuda Triangle Imbroglio

2.3 Gas Hydrate Emission Can Drown Ships—May’s and Monaghan’s Hypothesis

2.4 Carpet of Dark Gold Paved Over the Seafloor

Chapter 3: Complex Wave Motions and Thermal Structure of the Oceans

Abstract

3.1 Riddle of the Biblical Crossing of the Red Sea by Israelites Led by Moses

3.2 Invisible Colossal Waves Below Sea Surface—Internal Waves

3.3 Intricate Tidal Motions in Topographically Complex Water Bodies

3.4 Subsurface Warm Water Layer Sandwiched Between Colder Waters Above and Below—Thermal Inversion

Chapter 4: The Role of Oceans in the Origin of Life and in Biological Evolution

Abstract

4.1 Introduction

4.2 Darwin's Theory of Natural Selection

4.3 Subseafloor Microbial Life—Partial Clues to the Origin of Life

4.4 Organisms Living Above 100°C Under Anaerobic Conditions

4.5 Microbial Activity in Hydrothermal Fluids—The Zinc World Hypothesis

4.6 Significance of Deep-Sea Hydrothermal Vents

4.7 Homochirality of Amino Acids and Sugars

4.8 The 2015 Discovery of a Missing Piece of the Evolution Puzzle—Lokiarchaeota

4.9 The 2015 Discovery of a New Homo Genus Species

Chapter 5: Astronomical and Biological Organizational Relationships

Abstract

5.1 Fundamental Discoveries in Astronomical and Cosmological Sciences

5.2 Chemical Evolution Leading to the Origin of Life—Role of Primitive Oceans

5.3 Partial Clues to Origin of Life in Submarine Hydrothermal Vents

5.4 Chemical Evolution of Life-Supporting Structures

5.5 Origin of Life

5.6 Gene and Genetic Code

5.7 Horizontal Gene Transfer: A Story of Genetic Success

5.8 Safeguarding Genetic Information: The 2015 Nobel Prize Winning Discovery

5.9 Correlation Between Biological and Astronomical Organizations: Kumar's Hypothesis

5.10 Biological Evolution: The Role of Islands

5.11 Discoveries in Life Science: Cloning by Nuclear Transfer

5.12 Self-Organization in the Origin of the Universe and Biological Evolution

5.13 How Life Originated: A Puzzle to be Resolved

5.14 Religious Beliefs and Science

Chapter 6: Seafloor Hot Chimneys and Cold Seeps: Mysterious Life Around Them

Abstract

6.1 Introduction

6.2 Formation of Hydrothermal Vents

6.3 Tectonic and Magmatic Controls on Hydrothermal Activity

6.4 Serpentinization: An Important Set of Geochemical Reactions

6.5 Vent Fluid Composition and Temperature

6.6 Shallow Water Hydrothermal Activity

6.7 Deep-Sea Hydrothermal Activity

6.8 Iron Domination and Potential for Microbial Carbon Fixation: Loihi Plume

6.9 Biological Significances of Submarine Hydrothermal Vents

6.10 Unique Thermostable Enzymes in Hydrothermal Vent Worm

6.11 Exotic World of Marine Organisms Around Cold Seeps

6.12 Understanding the History of Benthic Organisms and Their Source of Food

6.13 Technologies Used for Hydrothermal Vents Studies

6.14 Conclusions

Chapter 7: Citadel-Building: Tiny Creatures in the Oceans—Corals

Abstract

7.1 Introduction

7.2 Coral Reefs and the Exotic Life on and Around Them

7.3 Coral Survey Techniques

7.4 Threat to Coral Reefs

7.5 Need for Conservation and Restoration of Coral Reefs

7.6 Ocean Acidification-Resistant Coral Reefs

7.7 Role of Tiny Crabs in Preventing Coral Death in South Pacific

7.8 Ancient Coral Reef Record Gives History of El Niño

7.9 Importance of Coral Reef Research and Management

7.10 An Experimental Platform for Direct Microscopic Study of Live Coral Polyps

Chapter 8: Marine Creatures With a Difference

Abstract

8.1 Introduction

8.2 Light-Capturing Pigment in Microscopic Marine Bacteria

8.3 Marine Organisms That Carry Living Light

8.4 Fishes That Play Hide and Seek

8.5 Marine Creatures That Mimic

8.6 Gelatinous Creatures

8.7 Lionfish: Decimator of Fish Populations and Threat to Coral Reef Ecosystems

8.8 Deep-Sea Vampire Squid: Thriving in the Oxygen Minimum Zone

8.9 Giant Squid and Colossal Squid

8.10 Life at Submarine Canyons and Deep-Sea Trenches

8.11 Dead Whales: Providing Deep-Sea Living Legacy

Chapter 9: Oceans: Abode of Nutraceuticals, Pharmaceuticals, and Biotoxins

Abstract

9.1 Introduction

9.2 Nutraceutical Products From Marine Flora and Fauna

9.3 Pharmaceutical Products From Marine Flora and Fauna

9.4 Immunotoxins and Biotoxins in Marine Flora and Fauna

9.5 Detection of Marine Biotoxins in Seafood

9.6 Conclusions

Chapter 10: Magic With Colors—Sea Surface Changes

Abstract

10.1 Introduction

10.2 Phytoplankton Bloom: Sea Surface Turning Green

10.3 Trichodesmium Bloom: Turning Sea Surface Brown

10.4 Coccolithophore Bloom: Turning Sea Surface Milky White

Index

Copyright

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Notices

Knowledge and best practice in this field are constantly changing. As new research and experience broaden our understanding, changes in research methods, professional practices, or medical treatment may become necessary.

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A catalogue record for this book is available from the British Library

ISBN: 978-0-12-809357-3

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Dedication

To my parents, who left this world years ago

Foreword

A multi-disciplinary book of this nature was long overdue for teaching and research and Dr. Antony Joseph has accomplished this commendable work. Providing ample references to original work, scientists, teachers, and students from various science disciplines will find this book extremely useful and interesting. Opening up a new window on multi-disciplinary research and teaching, Dr. Joseph has explored a wide range of topics, from the Earth's core and oceans' bottom, to deep inside the vast expanse of the universe. In doing so, he has critically analyzed the geological, geophysical, physical, geochemical, astronomical, astrophysical, biological, biochemical, and biomedical aspects.

His vast range of interests and his excitement about the topics have made this an interesting and useful book for teaching and research. He addresses all the topics with such equal expertise that it is difficult to determine to which discipline of science he belongs. His knowledge in every sphere is profound. He has worked painstakingly for the last four years to accomplish this great feat. My admiration for this book is great and I congratulate him for writing such an urgently needed book. If your interests extend to a complex range of topics from different disciplines of science, you'll find this book particularly helpful.

Dr. Antony Joseph is an eminent scientist who had a long oceanographic career associated with the CSIR-National Institute of Oceanography (CSIR-NIO), Goa, India, from February 1978 to July 31, 2012. While participating in oceanographic cruises onboard research vessels, he had opportunities to see remarkable marine creatures, examine the intricacies of the seafloor, and observe oceanographic processes, including valuable living and nonliving resources. Dr. Joseph has substantially contributed to the design and performance evaluation (both laboratory-scale and field-based) of ocean current and sea-level measuring devices. He led the establishment of an in-house designed sea-level station in Ghana, West Africa. The data measured from this station upon the arrival of the Sumatra tsunami in December 2004 contributed to understanding the global extent of this disastrous tsunami. He also helped establish a network of internet-accessible real/near-real time reporting sea-level, sea-state, and surface meteorological stations on the Indian coastlines and islands.

Apart from authoring this book, Dr. Joseph has written two other books, "Tsunamis: Detection, Monitoring, and Early-Warning Technologies" and "Measuring Ocean Currents: Tools, Technologies, and Data," published by Elsevier, New York. He has written several articles in the Encyclopedias and presented 41 research papers at various Science & Technology Conferences in India, France, Singapore, Japan, South Africa, Russia, Australia, and the United States. Dr. Joseph been published in IOC-UNESCO manuals and dozens of research papers in national and international journals of repute. He has delivered several dozens of talks in several countries. In addition, he was a faculty member at the Indian Academy of Scientific and Innovative Research while at CSIR-NIO.

This book has 10 chapters. As I went through the manuscript, I found it to be a unique endeavor. The topics addressed in this book are discussed in a way that even non-specialist readers with an interest in the starry sky, oceanic life, nutrition, pharmaceuticals, earthquake, tsunamis, etc., and curious about oceans, the seafloor and sub-seafloor can understand and enjoy. A large number of high-quality illustrations are included. Furthermore, text- and picture-specific websites are provided, giving additional resources and extend the chapters of the text to the internet's resources. I would like to now refer to some topics of the book.

In his chapter, Oceans' Role in Origin of Life and Biological Evolution, Dr. Joseph describes the mechanism of origins of life on Earth and subsequent biological evolution of humans (Homo sapiens) who are believed to be the only animal capable of critically understanding the world around them—a valuable goal in itself. The origin of life is a subject matter of intensive research for biologists, anthropologists, geologists, and cosmologists. Science now has evidence about the origin of the universe and the life supported by Earth and some clue about possible life on other planets and galaxies as well. Abundant life appears to have colonized this planet approximately 3800 million years ago (ie, 3.8 billion years ago (BYA)). Most durable bio-signatures have provided evidence and scientists concentrate on photosynthetic life, because its high primary productivity has left a very durable ancient record.

The origin of life is a long-standing and controversial subject, and different processes have been proposed. According to one, lightning in the early atmosphere and the consequent production of amino acids, when combined in long polymer chains, provided the basic constituents of life. The second concerns chemical processes at submarine volcanic vents which are thought to have been common in the Archean period (4–2.5 BYA), and life at those depths would have been shielded from the ultraviolet radiation that then existed due to the absence of an ozone layer. The third proposed mechanism has life originating from the carbon and hydrocarbons in comets and meteorites as they burned in the atmosphere. It has also been suggested life may have originated in inter-tidal pools that were repeatedly flooded and dried out under the sun—a process for which the geological record provides evidence.

The first known single-cell organisms called prokaryotes probably originated in the Archean period about 3.8 BYA in the oceans, when chemical composition of the ocean and the atmosphere was very different from today. Scientists have identified liposomes (pre-cellular systems) in which the encapsulation of DNA has been achieved using dehydration-hydration cycles similar to those that may have occurred in an inter-tidal setting on early Earth. Darwinian selection would have acted once self-replication of life was established and then evolution to more complicated forms of life could have taken place. Prokaryotes were the only form of life on Earth for millions of years until more complicated eukaryotic cells came into being through evolution. Microbial life has prevailed in the biosphere since the Archean period at least, and according to the most recent study, probably for the last 4.1 billion years.

The two groups of prokaryotes (ie, archaebacteria and eubacteria) are significantly different in cellular make-up and in their modes of evolution. There is now a general consensus among the Origin of Life scientists that the Last Universal Common Ancestor (LUCA) is the previous stage of prokaryotes. It is the most primitive organism from which all organisms now living are supposed to have evolved. The LUCA is estimated to have lived some 3.8–3.5 BYA. At about 3 BYA, something similar to modern photosynthesis developed and oxygen was produced. Over time, it transformed the earth's atmosphere to its current state. Some of the oxygen reacted to form ozone, which collected in a layer near the upper part of the atmosphere. By blocking the ultraviolet radiation, it allowed cells to colonize the surface of the ocean and ultimately the land.

This book provides an interesting discussion on the homochirality of amino acids and sugars. Homochirality is essential for the functioning of proteins as amino acid polymers, and for the structure of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), which requires incorporation of d-sugars. Appearance of homochirality in some biomolecules can apparently force corresponding homochirality onto others. It is believed that once d-sugars appeared in RNA, l-amino acids in protein might have been automatically formed. Emergence of this homochirality is a very important question in the mechanism of origin of life. How did this homochirality of amino acids and sugars arise? has been a puzzling question for scientists working on this mystery. All life known to exist on Earth today, and all life evidenced in the geological records, seems to be based on DNA genomes and protein enzymes (with exceptions of some RNA viruses). DNA is like a blueprint of biological information needed to build and maintain the living organisms. While discussing the DNA versus RNA in terms of identifying living cells, use of a highly sensitive molecular technique specifically targeting RNA as indicator of living cells in deeply buried marine sediments has been explained.

There are also detailed discussions on the leading RNA world theory of origin of life; arguing that before present life emerged, it was based solely on RNA. Strong reasons have been given to conclude that DNA and protein based life was preceded by simpler life forms based primarily on RNA, in which the genetic information was stored in the sequence of RNA molecules, and the phenotype derived from the catalytic properties of RNA. RNA was the first genetic molecule to form, providing a template to reproduce itself and make further molecules of life. Informational polymer RNA must have arisen by purely chemical means at some stage in the origin of life. The support in favor of RNA world hypothesis comes from the facts, including: (a) the central role played by different RNA molecules in the protein synthesis, (b) this process can take place in the absence of DNA, but not of RNA, and (c) the existence of replicating biological systems such as viroids and RNA viruses that use other single- or double-stranded RNA molecules to store genetic information. So, it is argued that genetic continuity was assured by the replication of RNA; and genetically encoded proteins were not involved as catalysts during the origin and evolution (development) of life on Earth. It is also interesting to view DNA as a modified RNA, because the components of DNA are synthesized from RNA components in modern biological systems. It was also assumed by the proponents of a RNA-world hypothesis that RNA-based life had been driven to extinction long ago with the arrival of superior DNA-based life.

According to some origin of life scientists, life may have originated when first of all RNA chains experienced the basic conditions (as conceived by Darwin) for natural selection to operate. These conditions are: (i) heritability, (ii) variation of type, and (iii) competition for limited resources. Fitness of an early RNA replicator would likely have been a function of adaptive capacities and the availability of resources. Three primary adaptive capacities could be: (1) capacity to replicate with moderate fidelity (resulting in heritability and variation), (2) capacity to avoid decay, and (3) capacity to acquire and process resources. These capacities would have been encoded in their nucleotide sequences. Their relative values of adaptive capacities would have determined the competitive success among different RNA replicators. RNA/vesicle systems that contain more genetic material (due to faster RNA replication) develop more internal tension than neighboring vesicles with less RNA, and draw membrane material from them. This would have allowed natural selection of vesicles by competition and control their own growth. Thus, for the first time, a system would have undergone Darwinian evolution by natural selection acting on variation and been a new and crucial emergent property arising at the transition from non-life to life. However, a superior DNA molecule is thought to have taken over the role of data (genetic information) storage due to its increased stability, while proteins, through a greater variety of monomers (amino acids), replaced RNA's role in specialized bio-catalysis. In contemporary life, we have our familiar DNA/RNA/Protein world we now inhabit.

However, there are also objections to the RNA world hypothesis. The central problem is to understand how a protein-free RNA world became established on the primitive Earth. It is far from obvious how ribonucleotides, building blocks of RNA, could have formed from their constituent parts (ie, ribose and nucleo-bases). The researchers have relied only on indirect hints to infer what RNA-based life was like. Some scientists believe that RNA-based life may not have been the first life to exist. It is believed that RNA may have played a major step in the evolution of cellular life, but this does not necessarily mean that first life was RNA-based. Evidence have been put forward that multiple self-replicating molecular systems preceded RNA. The main objections to the RNA-world hypothesis are: (i) RNA is too complex a molecule to have arisen prebiotically, (ii) RNA is inherently unstable, (iii) catalysis is a relatively rare property of long RNA sequences only, and (iv) the catalytic repertoire (skills) of RNA is too limited.

Dr. Joseph also explains the time period of clue for life on the Earth and Darwin's Theory of Natural Selection. Evidence for biological activity can be derived from carbon isotopes because a high C¹²/C¹³ ratio is characteristic of biogenic carbon. The microfossil record only extends to ~ 3.5 BYA and the chemo fossil record to ~ 3.8 BYA. Besides this, evidence of life on Earth is manifestly preserved in the rock record as well. Given the temporal limits of rock record (~ 4 billion years), the detrital zircons as old as 4.38 billion years have been documented. Zircons, serving as time capsules, can capture and preserve their environment. There are reports on C¹²/C¹³ of graphite preserved in 4.1 billion years old zircon grains imaged by transmission X-ray microscopy. The carbon contained in the zircon has a characteristic signature—a specific ratio of Carbon-12 to Carbon-13—that indicates the presence of photosynthetic life. Therefore, the most recent research reported in 2015 argues that the graphite's C¹² -rich isotopic signature may be evidence for the origin of life on Earth by 4.1 BYA, based on examination of zircons discovered from Jack Hills, West Australia. The discovery indicates that life may have begun shortly after the planet formed 4.54 BYA. Some scientists believe life arose relatively quickly on Earth; then by analogy, life could be common in the whole universe. The research further suggests that life in the universe could be abundant. Simple life on Earth appears to have formed quickly, but it likely took many millions of years to evolve the ability to photosynthesize.

Darwin's theory of natural selection proposed a mechanism by which all life could have descended from a common ancestor. Darwin propounded a plausible mechanism, natural selection, defined as the principle by which each slight variation of a trait, if useful, is preserved. According to some Darwinists, the common ancestor somehow evolved from nonliving matter, which is presumed to be some kind of dirty-water soup composition. Thus, submarine hydrothermal vents have become important to the origin of life studies. Charles Darwin showed that it is the gradualness of evolution through the natural selection process that allows formation of advanced/complicated life forms from simple ones. As for example, ancestors that look like bacteria can change into descendants that look like humans gradually over time, if given sufficient generations. As long as there is some variation between individuals and that variation is heritable, there will be an inevitable selection of individuals with most advantageous variations. If the variations are inherited, then differential reproductive success will lead to a progressive evolution of particular population of a species, and populations that evolve to be sufficiently different eventually become different species. Origin of Species was published in 1859, 23 years after Darwin returned from his long research voyage aboard the HMS Beagle. The concept was simple but powerful: individuals best adapted to their environments are more likely to survive and reproduce. Although Darwin's explanation of the causes of evolution had fallen out of favor among biologists during the first decades of the 20th century, the advent of molecular biology has advanced and accelerated the study of evolution by allowing direct examination of the genetic material that ultimately determines the phenotype (the set of observable characteristics of an individual resulting from the interaction of its genotype with the environment) upon which natural selection acts.

Scientists have proved recently that simple microbes found at the oceans' floors were our real ancestors. The discovery in 2015 of a group of microorganisms called Lokiarchaeota throws light as to from what type of microbial ancestor humans descend. Deep beneath the Atlantic Ocean, scientists have found microorganisms, Lokiarchaeota, which they call a missing link connecting the simple cells (prokaryotes) that first populated the earth to the complex cellular life (eukaryotes). These microorganisms inhabit the inhospitable, frigid seafloors and icy cold, oxygen-starved, hostile environment about 2.35 km under the ocean surface not too far (15 km) from a hydrothermal vent spewing fluids reaching about 300°C. The discovery of these rudimentary microbes from seafloor sediment layers was made during voyages of a Norwegian research vessel. Microbial life originated 4.1–3.8 BYA. The first complex cellular life appeared roughly 2 BYA. It has been one of the big puzzles of evolutionary biology how cellular complexity first developed from prokaryotes (bacteria and archaea) to eukaryotes (fungi, plants and animals, including humans). Lokiarchaeota share with eukaryotes several similar important gene characteristics, many of which have to do with cell membrane functions. Scientists are of the view that these genes are responsible in providing a Lokiarchaeota starter kit to support the development of cellular complexity.

The author has also explained the extinction events which affected life on Earth and the complexities of seafloors and oceans. He discussed such topics as sub-seafloor microbial life (partial clues to origin of life), organisms living above 100°C under anaerobic conditions (such as deep sub-seafloor sediments, submarine hydrothermal areas, and submarine volcanoes), significance of deep-sea hydrothermal vents, microbial activity in hydrothermal fluids, and a new Homo genus called Homo naledi, indicating the slow evolutionary transition from simple microbes found at the oceans' floors to more complex life forms that permeated the earth over a long period of time.

In the chapter on Astronomical and Biological Organizational Relationships, Dr. Joseph provides an account of our new understanding of the relationship between the organization and evolution of biological system and astronomical system, citing concrete evidence. Biological organization at the microscopic level (DNA molecule) and astronomical organization at the macroscopic level have striking resemblances. As a prelude to explaining this relationship, he first brings into focus the great strides made in astronomy, cosmology, and the working of the universe by extraordinary thinkers and visionaries such as Nicolaus Copernicus (1473–1543), Giordano Bruno (1548–1600), Johannes Kepler (1571–1630), Galileo Galilei (1564–1642), Sir Isaac Newton (1642–1726), Dr. Albert Einstein (1879–1955), Dr. Vesto M. Slipher (1875–1969), Dr. Alexander Friedmann (1888–1925), Dr. (Fr.) Georges Lemaitre (1894–1966), Dr. Edwin Hubble (1889–1953), Sir Arthur Eddington (1882–1944), and Dr. George Gamow (1904–1968). While appreciating the great contributions made by these visionaries, Dr. Joseph has also briefly pointed out in passing how science and technology have interacted with an adamant and intolerant religious society (particularly the Roman Catholic Church) in a life and death way during the 16th and 17th centuries.

The problem of origin, evolution, and the structure of the universe and life on Earth has always been an intriguing and exciting question for the scientists. According to Dr. (Fr.) Georges Lemaitre's Big Bang theory, the universe evolved with an explosion from a single point of matter with an infinite density and temperature at a finite time in the past, about 13.8 BYA. Self-organization in the origin and evolution of the universe (physical world) and life (biological world) has drawn much attention to these researchers. It is now generally accepted in scientific circles that the laws of nature are so self-sufficient that the complexity of the entire physical universe evolved from fundamental particles. Just as atoms, stars, and galaxies self-assembled out of the fundamental particles produced by the Big Bang, the laws of nature are self-sufficient enough to self-assemble life by chemical evolution of suitable molecules and structures, regardless of whether these laws are not designed or designed by God, as proposed by one school of thought. In the language of science embodied in Dr. (Fr.) Lemaitre's Big Bang theory, the universe evolved by self-organization of simple material structures towards more and more complex structures. Atoms, stars, and galaxies self-assembled out of the fundamental particles produced by the Big Bang. It has been suggested that, just like stars and their planets' satellites in the Universe—formed primarily from heavier elements such as carbon, nitrogen, and oxygen that were born in the explosions of supernovae—we, who consist primarily of these very same elements, are thus literally born from the stardust.

As indicated earlier, the process of biological evolution started from bacteria-like tiny cells, termed the LUCA, and gave rise to complex life forms on Earth, including human beings. It is very interesting and admirable that the satisfactory explanation offered by the Bing Bang theory of the origin of the universe, founded solely on Dr. Albert Einstein's "General Relativity theory and Hubble's cosmological measurements, gave a new dimension to the discussion on the topic of a totally different subject in science, that is, biological evolution of complex life forms from simple cells. Primitive life on Earth is believed to have happened just over 3.5 to 4.0 × 10⁹ years ago. Oparin in his book The Origin of Life," proposed that in prebiotic times, spontaneous generation of life would be less difficult if the ocean contained a large amount of complex organic components similar to those present in living organisms. These compounds would serve both as structural components and as the energy source for the first organisms. He also proposed that Earth had a reducing atmosphere of hydrogen (H2), ammonia (NH3), methane (CH4), and water (H2O) in its early stages, and that organic compounds might be formed under these conditions. Urey based his arguments for the reducing atmosphere on the thermodynamic properties of gases in a cosmic dust cloud from which the solar system was formed. He proposed that organic compounds might be synthesized by ultraviolet radiation and by electrical discharges (lightening) in the reducing atmosphere. Stanley Miller performed fundamental experiments using electrical discharges in a flask into which water vapor, H2, CH4, and NH3 had been injected and found that amino acids had formed, thereby strongly supporting the above theories. Since then, several other steps in the synthesis of organic molecules have been carried out and experiments simulating prebiotic conditions have yielded sugars, fatty acids, and nucleic acid bases. In continuation of these results, much research on chemical evolution and the origin of life have been carried.

A close relationship between the chemical evolution of life and the evolution of Earth's crust has been reported. It is argued that chemical evolution was followed by biological evolution, in which proteins were formed by polymerization of amino acids, and aggregates appeared in the water medium along with other organic compounds. Then, only after the origin of the genetic code, determined by the sequence of bases in nucleic acids—the first self-reproducing molecule, self-perpetuating cells could have arisen. Thus, self-organization of life first took place at the molecular level, for example, proteins, nucleic acids (RNA and DNA). Following the evolution of the first cell on the Earth (ie, prokaryotic cells, which did not have distinct organization of nucleus), organization of nucleus took place in eukaryotic cells, which evolved from prokaryotic cells. Subsequently, from the lower forms of unicellular living organisms evolved all the higher forms of complex multi-cellular living organisms, spearheaded by modern humans. It is now a well-established fact that the genetic code has played a key role throughout the evolutionary process and acted as an intracellular computer in the organization of the cells, tissues, organs, and the whole organisms.

As Dr. Joseph explores in his chapter on Astronomical and Biological Organizational Relationship, I, too, have touched on, reported, and discussed some aspects of correlation between biological organization at microscopic level and astronomical organization at macroscopic level; and found an underlying unifying relationship between two seemingly different disciplines of science. Based on the latest estimates, there exist about 8.7 ± 1.3 million different species of organisms on Earth; at the cellular and molecular levels, there is a unique master plan of organization common to all. All organisms have the cells as their basic structural and functional unit and all have essentially the same genetic code made of DNA. The light, scanning, and transmission electron microscopic studies have shown that cells of a particular type are organized together to form a tissue of specialized function, and different tissues are organized to form organs to perform a particular function in an organism. There is also a definite organizational plan in our solar system and galaxy, other galaxies, and cluster of galaxies of the expanding universe as revealed by telescopic and astrophysical investigations in every band of the electromagnetic spectrum. However, little has been done to investigate a relationship between the microscopic organization of living organisms and the astronomical organization. My investigation implies that the two parts of nature—biological world down to microscopic level and physical world at macroscopic level—are intimately correlated; a fact which has always been overlooked. The investigation points out a definite correlation between the organizational plan of DNA molecule and cells during organic evolution and the organizational plan of our solar system during inorganic evolution. The following equation, showing the correlation between the genetic code of DNA molecule and the apparent motion of the Sun—due to Earth's revolution around the Sun—has been derived by me and reported: (64 − K)/20 = 339/107.65, where 64 = number of codons; 20 = number of amino acids; K = astro-molecular constant derived in my paper; 339 = number of disks of the sun to measure its apparent path along the ecliptic in the celestial sphere between the two equinoxes; and 107.65 = average distance of the sun in terms of its own diameter from Earth.

All living organisms on the earth share the same 64 codons and 20 amino acids. The above equation correlates the biological molecular data with the astronomical data, thereby implying a common organizational plan of the DNA molecule and our solar system, probably due to the influence of a common governing force, that is, gravitational force and waves. In the framework of Dr. Einstein's General Theory of Relativity, the properties of space, time, and gravitation are merged into one harmonious and elegant picture. Dr. Albert Einstein propounded the idea of gravitational curvature of the four-dimensional space-time continuum. This correlation also suggests that all natural self-assembly—from microscopic to macroscopic world (microcosm to macrocosm)—are probably influenced and controlled by gravitational curvature of space-time, as for example, self-assembly of the solar system and DNA double helical molecule. Scientists have long used mathematics to describe the physical properties of the universe. But cosmologist Max Tegmark believes that the universe itself is mathematics. In Tegmark's view, everything in the universe, humans included, is part of a mathematical structure. In his book, Our Mathematical Universe, the M.I.T. physicist Max Tegmark describes two important aspects—one is an informative survey of exciting recent developments in astrophysics and quantum theory, and the other is a discussion of his innovative idea that reality itself is a mathematical structure. DNA and life originated and evolved in the gravitational curvature of the fabric of space-time caused by the sun's large mass and Earth's mass as proposed in Einstein's General Theory of Relativity. It is truly gratifying that Dr. Einstein's last prediction about gravitational waves was confirmed on February 11, 2016, a century after his prediction.

The world line (path of an object in Dr. Einstein's space–time) of orbital motion of the Earth is a helix and geodesic (curved 4-dimensional space-time). It is tempting to speculate that there could be a correlation between the helical world line of Earth's orbital motion and the helical structure of the DNA molecule, which is the first self-reproducing double-helical molecule to have formed in the beginning of evolution of life. The large gravitational force, due to the curvature of Dr. Einstein's space-time, exerted by the sun not only holds the members of the solar system together, but also causes them to take part in its true movement, that is, a movement relative to the adjacent fixed stars and a revolution (cosmic year) about the center of the galactic system, which itself is moving in the space. It is interesting to propose that cosmic year might cause biological rhythms (cosmic rhythms) on the Earth in a large scale of time. We know that the diurnal rhythms (circadian rhythms) and annual rhythms observed in the activities, distribution and physiology of the living organisms are related to the time of the day on a 24-h basis (due to rotation of the Earth) and season of the year (due to revolution of the Earth around the sun, and the Earth's axis being tilted by 23.5 degrees with respect to the ecliptic).

The data of my investigation shows that the microscopic numbers—that is, the number of codons in the genetic code of DNA, number of amino acids specified by these codons, which are common to all organisms—are functions of the astronomical numbers as shown in the above equation. It also implies a close relationship between the organizational plan of DNA molecule, cells, tissues, organs, and the whole body of the organisms during organic evolution and the organizational plan of different planets in the solar system, galaxies, cluster of galaxies, and the whole universe during inorganic evolution. If intelligent life exists elsewhere in the cosmos, it is likely that the basic structural organization of genetic code and cell, tissue, and organ systems would be the same as on Earth because of the universal gravity acting in the cosmic fabric of space-time. Several works on supermassive star have opened up a new field in astrophysics, called relativistic astrophysics, where Newtonian gravity is replaced by Dr. Einstein's General Theory of Relativity. Dr. Einstein has also suggested that gravitational fields play an essential role in the elementary formations which go to make up the atom. Different combinations of the same atoms, obeying the same laws, compose both the inanimate and the living worlds. The evidence has been presented that virtually all electrons and nuclei of the atoms, that are or have been part of living matter on Earth, come from almost all stars in our and nearby galaxies, and even from all other galaxies in the universe. Many scientists, who believe in an underlying order in nature, search for an ultimate, unifying principle in the physical sciences as well as in biological sciences. My astrobiological investigation suggests gravitational force and waves due to warping of the cosmic fabric of space-time as a unifying force/entity between the biological science and physical/astrophysical/chemical sciences.

Thus, we see a close correlation between the microscopic world (microcosm) and the astronomical world (macrocosm). Inorganic evolution of the physical universe and organic evolution of biological universe may be seen to represent nothing but two different facets of the same cosmological phenomenon called gravitation due to warping in the fabric of Dr. Einstein's space-time continuum. The just-mentioned astrobiological investigation suggests a possible continuity from microcosm to macrocosm—that is, from the tiny world of the atom to the vastness of universe through the integrated levels of organization, including all living organisms. These findings may open new vistas in our understanding of the origin, evolution, and structural organization of the universe. The advent of a new generation of astronomical instruments opens new windows for the astronomers, and may call for major revisions in the standard view of cosmology. My proposition is that an extensive and well-coordinated work between different types of microscopes and telescopes would be able to reveal more mysteries enveloping the microcosm and macrocosm; and thus further bridging the presently existing gaps between various scientific disciplines, such as biology, chemistry, and astronomy/astrophysics. The organization of life is key to the organization of physical universe. I propose that knowing the biology better would solve the mysteries of the universe better.

As a post-doctoral investigator in the department of anatomy at All India Institute of Medical Sciences (AIIMS), New Delhi, the Light, Scanning and Transmission Electron Microscopic structures of different types of cells and tissues observed during my studies and their comparison with telescopic pictures of our solar system and galaxy, other galaxies, cluster of galaxies in the universe taken by me and others, implies that the physical universe very much resembles the living system. Astronomers have taken the pictures of interconnecting filaments of star clusters and clusters of galaxies that form the texture of the universe and connect our galaxy to the vast expanse of the universe. One of these filaments of groups of galaxies and star clusters surrounded by immense voids is considered to be akin to the umbilical cord that fed our galaxy during its youth. Many phenomena—involving stars, nebulae, galaxies, cluster of galaxies, and black holes—occurring in the universe, seems to be analogous to the phenomena occurring in the living system. These analogies existing on the two different scales of space and time might appear unrelated initially. DNA, the blueprint of all living organisms on the earth, is involved in the structural organizations and all vital functions, such as protein synthesis and production of energy. It is tempting to speculate that the universe may have a blueprint for structural organizations and functions of the universe. A new and exciting vista is open for the exploration of the universe and biomedical science.

In discussing the Chaotic and Vibrant Seafloor, Dr. Joseph has assembled a comprehensive and scholarly account of the overall composition of Earth, covering the reversal of its magnetic field and the consequences of such repeated events, followed by a brief description of the discovery of the formation of different continents from one big land mass, and the clues put forward by several schools of thoughts, which finally led to the development of plate tectonics theories that succeeded in unifying continental drift and seafloor spreading notions. He also provides a brief discussion on Earth's formation, Earth's interior, earthquakes, volcanic eruptions, oceanic ridges and seamounts, seafloor spreading, plate tectonics, triple-plate junctions, submarine trenches, canyons, hot spots (fixed points on the Earth's surface defined by long-lived volcanism), submarine hot-fluid spewing chimneys, and cold seeps. The author believes that this approach would be useful in providing a framework for evaluating the evolution of viable ecologic niches on this planet. So a glimpse of the geological history of early Earth and its gradual evolution from its initial hot and entirely gaseous lifeless state to the present lively state has been given.

"Big Bang took place approximately 13.8 BYA when all of space was contained in a single point" which, in an explosion, gave birth to the universe. The heaviest elements were formed in the explosions of supernovae. In first-generation stars, heavier elements such as carbon, nitrogen, and oxygen were formed. Aging first-generation stars then expelled them out into space. The forces of gravity subsequently allowed for the formation of newer stars and of planets. The formation of the solar system began approximately 4.6 BYA with the collapse of a small part of a giant nebula. Most of the collapsing mass collected in the center, forming the sun, while the rest flattened into a proto-planetary disk out of which the planets, moons, asteroids, and other small solar system bodies formed. The surface of a fire ball of hot gases consisting of rock vapor clouds (Proto-Earth) started cooling since its birth. The Proto-Earth collided with a Mars-sized projectile some time before 4.5 BYA. Vaporized rock, mainly from the projectile, condensed in orbit to form the moon. The rock vapor clouds of the Proto-Earth radiated heat to space, thereby cooling the planet to liquid rock in approximately 1000 years. Thus, the early Earth was fully molten. Further cooling resulted in its present form of a flattened sphere called Earth. Water clouds condensed at the top of atmosphere and heat radiated to space. From 4 to 3.8 BYA, Earth underwent a heavy bombardment by asteroids. Steam escaped from the crust while more gases were released by volcanoes. Clouds formed as the planet cooled. Rain gave rise to the oceans about 3.8 BYA, or even earlier. Carbon dioxide (CO2) being a greenhouse gas, Earth's surface could not have cooled to habitable conditions without the sequestration of atmospheric CO2 as carbonates in hot rocks. The Earth's surface was pleasant at about 30°C, only when approximately 1 bar of atmospheric CO2 remained.

The interior structure of the Earth consists of several layers like an onion. The information about the interior structure of the Earth is collected by geologists from several different sources. Some rocks found at the Earth's surface originated deep in the crust and mantle. Geologists derive some idea from these rocks about the composition of the interior of the Earth. Another source of information is earthquake, or seismic waves which is more indirect, but perhaps more important. When an earthquake occurs anywhere on Earth, seismic waves travel outward from the earthquake's epicenter. The speed, motion, and direction of seismic waves changes dramatically at different levels within Earth, known as seismic transition zones. Therefore, scientists can make various inferences about the Earth's character above and below these transition zones through careful analysis of seismic data. The present Earth is endowed with a thin surface layer of rock called the crust that covers the globe, whose 70% area lies below the oceans.

At the center of the Earth, temperatures are as high as they are on the surface of the sun (approximately 7000°C). Over billions of years, this has caused continents to drift apart and, consequently, the oceans to open and close. The study of Earth and the oceans that feed us and control the Earth's climate are fundamental to our understanding of the precious balance of life on Earth.

In this book, the author has also described and discussed various kinds of triple junctions on the seafloor, rotating microplates and the discovery in 2015 of the first oceanic microplate in the Indian Ocean. Formation of submarine mountain chains, seamounts, island arcs, mud-volcanoes, canyons, and trenches are also briefly addressed. Finally, the chapter winds up with a discussion based on analysis of results from an ocean drilling experiment.

Dr. Joseph describes two very interesting aspects concerning abyssal depths of the oceans; one is the Bermuda Triangle imbroglio that is specific to the Atlantic Ocean, and the other is the formation of polymetallic nodules that are common to the Pacific, Indian, and Atlantic Oceans. While discussing the Bermuda Triangle imbroglio, some related aspects, such as the historical episode of fire breakout in the Japan Sea, trawler wreck in Witch's Hole pockmark in the North Sea in the Atlantic Ocean, and methane hydrates have been very nicely explained. Large amounts of methane gas in the form of gas hydrate are trapped below the seafloor at different regions at different depths. Hydrates are unstable and tend to dissociate rapidly due to the presence of a large empty cavity at the core of their structure. Gas hydrates are clathrate compounds. Clathrate is a structure in which water molecules, under certain conditions, bond to form complex networks of molecules forming cagelike structures that encapsulate a guest molecule, which is a gas. When that guest is a methane molecule, it forms a methane hydrate. Methane hydrate deposits in the seafloor sediment layer and their role in the Bermuda Triangle imbroglio is discussed, as well as the possible influence of the warm Gulf Stream in triggering methane gas emission, which, based on scientific evidences, is suspected to be the culprit in the sudden disappearances of ships and low-flying aircrafts in the Bermuda Triangle region, earning it the nickname The Devil's Triangle.

Studies supported by submersibles have reported having witnessed methane gas bubbles forming on the seafloor and gradually rising to the sea surface. In the beginning, the bubbles are smaller in size, but as they go up, they keep growing in size because of the continuously decreasing water pressure in the neighborhoods. These gas plume bubbles become so big at times that they get much larger than a large ship. When the ship passes over the plume, the ship is completely engulfed and sinks down to the bottom of the sea. If the gas flow was large, a plume of free gas would rise above the sea surface as gas clouds. Any low-flying aircraft passing through the concentrated gas clouds could be suffocated and would experience engine failure and might crash.

The illustrious navigator Christopher Columbus, who discovered America, sighted a strange light in 1492 in the Bermuda Triangle region. After that event, until 2009, nobody is known to have reported spotting strange lights in the sea. But in July 2009, a paper (authored by Drs. Tsuji and Tachibana from Japan) presented at the 24th International Tsunami Symposium, held at Novosibirsk (Siberia, Russia) describing the Japanese historical accounts (which remained buried in the Japanese language archives) of fire having broken out in the Japan Sea in 1854 and 1946, delighted every delegate to such a great extent that at the end of the talk everybody stood up in awe, and profusely clapped in great appreciation of the Japanese authors for breaking this new piece of information to the world. The author of this esteemed book was one among the delegates to witness this great moment.

The author addresses another interesting aspect of the ocean floor, namely; the carpet of dark gold (poly-metallic nodules) having been paved over it by nature over a period of billions of years' utterly slow growth (at the rate of 1–3 mm/million year). This is a totally unrelated, but fascinating, fact about the oceans, where the abundance of a special kind of an approximately potato-shaped, multimineral form, known as poly-metallic nodules—which cover vast areas of the seafloor, but are most abundant in abyssal oceanic basins at water depths of 4000–6500 m—has been very nicely described and discussed. These nodules vary in size, from tiny particles visible only under a microscope, to large pellets more than 20 cm across. However, most nodules are between 5 and 10 cm in diameter, about the size of potatoes. Their surface is generally smooth, sometimes rough, knobby, or otherwise irregular. It was found that there are some regions in the world oceans where the seafloor is so strewn with nodules of differing shapes and sizes that the seafloor looks like a vast carpet of dark gold. The nodules contain commercially attractive (though variable) levels of metals such as nickel, copper, and cobalt.

The author attaches due importance to the devices used for collection of the dark gold from the abyssal ocean depths (paved on the ocean floor, as well as buried in thick sediments lying below the ocean floor's water-sediment interface). Subsequent discussion on the dark nodules revolve around important aspects, such as their specialty and structure, factors influencing their formation, the role of nucleating materials, their shape and surface texture, internal features (thickness of oxide layer; internal micro-structure), chemical composition, role of microorganisms in their formation, and presence of rare earth elements. The distribution of nodules in the world oceans reported by numerous scientific and industrial research programs undertaken by various organizations, particularly the Indian National Institute of Oceanography (CSIR-NIO), has been comprehensively discussed.

Oceans as an abode of nutraceuticals, pharmaceuticals, and biotoxins has been described in detail and presented by Dr. Joseph. The environment in the oceans is an exceptional reservoir of bioactive natural products, many of which exhibit structural and chemical features not found in land-based natural products. Marine organisms have evolved biochemical and physiological mechanisms, such as production of bioactive compounds for diverse purposes, including survival, reproduction, communication, and protection against predation and infection, and competition.

Because of the peculiar physical and chemical conditions in the oceans, marine organisms produce within them a variety of molecules with unique structural features. The sea also provides amazing biological diversity besides the chemical diversity. In terms of biodiversity, the oceans are far more diverse and really would have been the better place to start developing a natural pharmacy. The possibility of medicinal breakthrough discoveries from the marine world has radically increased in the last few years and paralleled the advances in biotechnology.

The quest for anti-cancer marine alkaloids (class of nitrogenous organic compounds, primarily of plant origin, including many drugs and poisons which have pronounced physiological actions on humans) and the discoveries made until now in this field are quite striking, especially when considering the short exploration time. Significant efforts were undertaken to isolate these bioactive secondary metabolites from marine flora and fauna. Cyanobacteria, fungi, sponges, algae, and tunicates have proven to be a source of a large array of alkaloids, many of which can potentially compete with anti-cancer alkaloids derived from plants, and which are in clinical trials or in clinical use. Although the majority of these secondary alkaloids were identified in cyanobacteria, the most studied ones are from sponges and tunicates. It was found that alkaloids derived from sponges and tunicates have various anti-cancer activities. Two alkaloids derived from tunicates—aplidin and trabectedin—are already in phase II cancer clinical trials. Several modes of action of marine-derived alkaloids are similar to those of their terrestrial counterparts, while others have completely novel mechanisms. Despite the recent advances in drug discovery from marine organisms, the marine environment is still to be considered a relatively untapped resource, particularly for discovering promising anti-cancer drugs. The marine organisms, which have had to endure predation and stressful habitats over prolonged years of evolution, hold great promise for the future of anti-cancer drug discovery. Successful collaborations between academic institutes and pharmaceutical companies will continue to provide the mutual benefits that each party seeks. The marine natural products have an exceedingly bright future in the discovery of life-saving drugs. The pharmaceutical industry now accepts the world's oceans as a major frontier for medical research. The pharmaceutical companies, such as PharmaMAR (Spain & United States), Aventis, AquaPharm Biodiscovery Ltd. (United Kingdom), Nereus Pharmaceutical (United States), Neurex, Novartis, and Wyeth are working in the field of marine natural products.

Drug discovery from marine natural products has enjoyed a renaissance in the past few years. Ziconotide, a peptide originally discovered in a tropical cone snail, was the first marine-derived compound to be approved in the United States in December 2004 for the treatment of severe, chronic pain in patients who require intrathecal analgesia. In October 2007, Trabectedin became the first marine anti-cancer drug to be approved in the European Union. Seven therapeutic agents (four anti-cancers, one anti-viral, one for pain control, and another for hyper-triglyceridemia) have been reported to be derived from the marine environment. In addition, a further 13 agents are in phase-I, II, or III clinical trials. Marine mollusks, sponges, and tunicates are the richest collected source of these most valuable substances. However, these animals have been shown to be or are strongly suspected of harboring or feeding upon microorganisms that are the actual producers of the bioactive agent. Some 13 agents with a marine origin are in current clinical trials, 11 with an indication for cancer cure, one for cognition and schizophrenia, one for Alzheimer's (along with cancer) treatment, and one for wound healing. Interestingly, three of these agents (one in phase-II and two in phase-I trials) are antibody conjugates.

Immunotoxins and antibody-drug conjugates are protein-based drugs combining a target-specific binding domain with a cytotoxic domain. Such compounds are potentially therapeutic against diseases including cancer; and several clinical trials have shown encouraging results. During the preparation of immuno-conjugates by chemical synthesis, the choice of the hinge component joining the two building blocks is of paramount importance: the conjugate must remain stable in vivo, but must afford efficient release of the toxic moiety (ie, an anti-cancer drug molecule) when the target is reached. There are many strategies employed in developing immuno-conjugates focusing on the evolution of chemical linkers. Three components are essential—a targeting agent, a biodegradable linkage, and a bioactive potent anti-cancer agent. Several aspects of the rational design of active conjugates may be of interest. Antibodies alone have shown some success in extending the lives of cancer patients, but in many cases, more potent agents are required to attempt complete eradication of the cancer mass. Many different agents have been conjugated, including traditional anti-cancer agents, cytotoxic natural products, phytotoxins, radioisotopes, bioactive proteins, enzymes that activate pro-drugs of cytotoxic agents, and photosensitizers. In order to exploit the maximal effect, the inherent potency of the released drug must be sufficient to kill the tumor cell, even at low concentrations. To achieve significant cytotoxicity, very potent agents must be used. Antibody-based therapeutics is of growing significance in cancer therapy, as evidenced by the fact that 28 such drugs have now been approved for oncologic indications by the FDA, for marketing in the United States. The market for these therapeutics is the fastest growing sector in the pharmaceutical industry. Thus, the pipeline of promising marine-derived or inspired agents is very strong. Seven agents have entered the clinic as approved drugs, mostly in the area of cancer, but also for viral, pain and hyperlipidemia indications. When combined with the rich pipeline of agents in clinical trial and preclinical evaluation, it can be surmised that the marine environment has performed extremely well in yielding new medicines, as well as pharmacological tools. Keeping in view the actual or suspected metabolic source of the most important agents, the heterotrophic bacteria and cyanobacteria are the real metabolic jewels of the world's oceans; accounting for fully 80% of these clinical trials and approved pharmaceutical agents. A number of commercial providers offer marine natural products for sale as research biochemicals. The sponges, cyanobacteria, and algae/plants (micro-algae, macro-algae, and aquatic plants) are the sources of most of these useful tool compounds.

The first living organisms are believed to have appeared in the oceans more than 3.5 BYA and evolutionary development has equipped many marine organisms with the appropriate mechanisms to survive in a hostile milieu, in terms of extreme temperatures, changes in salinity, and pressure, as well as overcoming the effects of mutation, bacteria, and viral pathogens. Many sessile invertebrates such as sponges, corals, and tunicates feed by filtering seawater. Because seawater contains high concentrations of bacteria, these organisms produce antibiotics to defend themselves from potentially harmful microorganisms. Thus, the production of antibacterial compounds by microorganisms and filter-feeders such as sponges, mollusks, bryozoans, ascidians, etc. provides a possible link between chemical defense for the marine organisms and antibiotics for use in humans. The researchers are concentrating their efforts on slow-moving or sessile invertebrate phyla that have soft bodies, and lack spines or a shell, that is, animals that require a chemical defense mechanism for their survival.

The search for Drugs from the Sea progresses at the rate of a 10% increase in new compounds per year. Researchers have isolated several nucleosides from the Caribbean sponge Tethya crypta (Tethylidae). This discovery led researchers to synthesize analogues, Ara-A and Ara-C, which improve antiviral activity. These marine-related compounds are in clinical use. Ara-A is the acronym for Adenine arabinoside. This is an analogue of adenine and acts by inhibiting DNA polymerase, so that viral DNA synthesis is inhibited. It is effective against herpes viruses, varicella-zoster virus, vaccinia, and hepatitis B viruses. Arabinosyl Cytosine (Ara-C) is a chemotherapy agent used mainly in the treatment of cancers of white blood cells, such as acute myeloid leukemia and non-Hodgkin lymphoma. Ara-C kills cancer cells by interfering with DNA synthesis. Ara-C and Ara-A were the first commercialized drugs of marine origin. Some other early successes were the discovery of prostaglandins and cephalosporins, and production of a cervical dilator from seaweed of the Laminaria genus. Systematic efforts and leads for drug development were greatly helped by the development of new technologies in diving, sample collection, chemical analysis, and biological screening. It is worth noting that more than 7000 marine natural products have been isolated and many leads have been obtained which have resulted into some drugs being commercialized, either as semi-synthetic derivatives of the original marine chemicals, or completely new synthetic compounds. Analysis of the source of these natural products indicate that approximately 25% are from algae; 33% from sponges; 18% from sea whips, sea fans, and soft corals; and 24% from other invertebrate phyla such as tunicates, mollusks, starfish, sea cucumbers, and moss animals.

The major advantages of marine drugs are their effectiveness in patients who have become resistant to the drugs developed from land-based plants or synthetic materials. The oceans, which offer a biologically rich ecosystem that covers approximately 70% of the Earth, contain a large number of organisms, which produce an array of compounds to help them withstand extreme conditions of temperature and pressure, and to provide protection against predators. One class of these compounds is the nitrogen-containing alkaloids. Recently, marine-derived alkaloids, isolated from aquatic fungi, cyanobacteria, sponges, algae, and tunicates, have been found to also exhibit various anti-cancer activities. The molecular revolution has forever changed the face of marine natural products chemistry. With the genomics, proteomics, metabolomics, and transcriptomics being employed by marine natural product practitioners, new areas of science and inquiry have emerged over the past decade that have begun to answer long-standing questions and provide fresh ideas for new research directions. The linking of natural products chemistry with modern molecular biology has empowered researchers with the ability to address fundamental questions about the biosynthetic capacity of marine organisms, the synthetic role of microbes in marine invertebrate natural product chemistry, and the bio-engineering potential of marine drugs.

In recent years, a significant number of novel metabolites with potent pharmacological properties have been discovered from marine organisms. Notable discoveries were made of compounds that profoundly affect the cell cycle and cellular metabolism. For example, hymenialdisine, a marine sponge constituent, is capable of inhibition of cyclin-dependent kinases, gsk-3beta, and ck1. Likewise, aldisine alkaloids from the Philippine sponge stylissa massa are potent inhibitors of mitogen-activated protein kinase-1 (mek-1). It seems that the future looks almost hopeful in developing a whole new pharmacopoeia from the sea. The oceanic world has much to offer human society in terms of pharmaceutical agents,