Answer:
For early earth, it was filled with loads of oxygen and could kill humans if they breathed the oxygen that was in the air about 100 million years ago. This massive amount of oxygen cause massive creatures like the dinosaurs to exist. Current earth has an atmosphere with not too much oxygen.
Explanation:
brainliest
Answer:
In general, negative selection eliminates from the population very harmful changes to proteins that kill or stop reproduction. ... The authors also found a correlation between genes predicted to be under negative selection and genes implicated in certain hereditary diseases
Explanation:
Which proposes that once species<span> appear in the </span>fossil record<span> they will become stable.... i think i just wanted to help......</span>
The answer is A
This is because 90% of energy is lost when we go up one trophic level. This means that even the the consumers tend to be larger in size, they are fewer in number and need to eat more in order to sustain themselves.