The following ayat from Surah Al-Baraqah Ver 28 strucked me deeply in relation to why and how Allah created all living things in this world and how we perceived them as a Muslim.
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26. Verily, Allâh is not ashamed to set forth a parable even of a mosquito or so much more when it is bigger (or less when it is smaller) than it. And as for those who believe, they know that it is the Truth from their Lord, but as for those who disbelieve, they say: "What did Allâh intend by this parable?" By it He misleads many, and many He guides thereby. And He misleads thereby only those who are Al-Fâsiqûn (the rebellious, disobedient to Allâh).
Clearly, in any creation by Allah big or small, there is always something that we can learn and ponder upon. Only our iman will lead us to full admiration of Allah or total disregard of His might. Wallahua'lam.