Extinction.
Rosie noted regretfully that Bob's worst characteristic was his lack of adaptability--he wouldn't even consider a wedding in Antarctica!
Adaptability.
The cold and lack of light killed plants, which killed off certain small animals, which killed off some of the animal that ate small animals.
Snakes and fish are examples of animals that lack external ears.
adaptability
how lack of service delivery will lead to pollution
There are quite a few animals that contain tissues but lack complex organs. One of these animals is the jellyfish.
they're not
adaptability is key to long term survival of any animal species
Cloning as a means of reproduction for lower animals and plants in nature is common. In these cases the negative is that it leads to low genetic diversity in the population as a whole and a general lack of adaptability. Amongst some higher animals, research is still in its infancy but the very few clones that have been produced have shown reduced life expectancy and poor general health.
Of course bettas can see, so long as animals have eyes they can see. However, ammonia poisoning due to lack of tank care can lead to blindness in fish.
Animals lack the ability to reproduce asexually and they can't decompose dead things. Animals are not emo unlike fungi and protists some protists single celled