Day 4 of Ramaḍān
Animals who walk on Fours
 
وَاللَّهُ   خَلَقَ كُلَّ دَابَّةٍ مِنْ مَاءٍ فَمِنْهُمْ مَنْ يَمْشِي عَلَى بَطْنِهِ وَمِنْهُمْ   مَنْ يَمْشِي عَلَى رِجْلَيْنِ وَمِنْهُمْ مَنْ يَمْشِي عَلَى أَرْبَعٍ يَخْلُقُ   اللَّهُ مَا يَشَاءُ إِنَّ اللَّهَ عَلَى كُلِّ شَيْءٍ قَدِيرٌ٤٥
And Allah has created every animal from water. Some of them   move upon their bellies and some of them move upon two feet and some among them   move upon four. Allah creates what He pleases. Verily, Allah has Power   over all things.[1] 
Commentary
NUMBER 4: In this verse which speaks about the creations which Allah has put on the earth, another sign of His Oneness (tawḥīd), is pointed out - the life which He has given to various creations. 
He begins by one of the scientific realities of creation and tells us that He has created everything from water. It is interesting that NASA’s motto in the hunt for extraterrestrial life has been “follow the water” – if there is water, there is a good chance that life exists. However from water - this one source of life - it is amazing how diverse the creations are that Allah has gifted us with. 
In this verse, He shows us that some of His creations crawl on their bellies – creatures like the snake which have no arms or legs or appendages; then Allah tells us that some creatures have two feet like us human beings; and lastly the All-Knowing tells us that some animals move about on four feet. 
It should be noted that there are many animals which are NOT mentioned here – there is no talk about the birds which fly; and nothing about the sea creatures, or insects with tens if not hundreds of ‘legs’ - so is this verse incomplete? 
The point of such verses is not to give us a detailed explanation of the entire animal kingdom – for we could do that by going outside and exploring nature, but rather, as He says at the end of the verse, Allah creates whatever He wills – and He cannot be controlled or stopped in His workings. In summary, there is much more out there that He did not speak about … but then the Quran is not a book of zoology or an encyclopedia of what exists on Earth. 
At the end of the verse Allah says that He has the power to do anything that He wants, so we must submit and accept the fact that there is much more out there that we have not discovered yet, or that He has not informed us about.
Point of Reflection
If we as human beings are not on the road of discovering Allah, treading the path of spiritual elevation or proximity to the Creator, and are not trying to become better humans, living up to our fullest potential, then we are no better than the animals which He creates.
    
[1] Quran, Sūrah al-Nūr (24), Verse 45.