3
votes
4answers
247 views

Are we inevitable in the evolution?

Suppose we wind time back to the instance when life emerged on Earth and let evolution start over again, will human beings or any other kind of self-conscious animals evolve ultimately, inevitably? ...
3
votes
1answer
55 views

Chemoautotrophy in large organisms?

The major nutritional mechanisms include chemoautotrophy, heterotrophy (including parasitism and saprotrophy) and photoautotrophy. All of these modes of nutrition developed first in prokaryotic ...
2
votes
1answer
51 views

Does the existence of one species imply the existence of many other?

Reading one of Sir Arthur Clarke's scifi stories, I came across a statement something to the effect of, existence of a single species automatically implies the existence of many other species. So ...
12
votes
3answers
505 views

Why are there no organisms with metal body parts, like weapons, bones, and armour? (Or are there?)

Reading this question, Why are there no wheeled animals?, I wondered why no organisms seem to make use of the tensile and other strengths of metal, as we do in metal tools and constructions. I am ...
28
votes
3answers
1k views

Why are there no wheeled animals?

In physics, "almost everything is already discovered, and all that remains is to fill a few unimportant holes." (See Jolly.) Therefore, on Physics SE, people are veering off into different directions: ...
18
votes
5answers
633 views

Why did life not evolve to use radio?

We use electromagnetic communication everywhere these days. Cell phones, wifi, old-school radio transmissions, television, deep space communication, etc. I'm curious about some of the possible ...
3
votes
2answers
305 views

Why Didn't Evolution Cause the Human Body to become Streamlined?

If streamlining makes movement/locomotion quicker and easier, why didn't the apes evolve into life-forms that had streamlined bodies (much like fish)?
36
votes
4answers
2k views

Why do plants have green leaves and not red?

I know plants are green due to chlorophyll. Surely it would be more beneficial for plants to be red than green as by being green they reflect green light and do not absorb it even though green light ...