Explanation:
NUTRITION AND AGE FACTOR!
Answer:
That is quite a gene pool you two have
Explanation:
Two chambers - fishes (atrium and ventricle)
three chambers - amphibians (two atria and ventricle)
also reptiles have three chambers with incomplete separation in ventricle
crocodiles, birds and mammals have four chambers - two atria and two ventricles (complete separation)
other differences: arthropods and many other groups of invertebrates have an open circulatory system which means that vessels are open and blood/other fluid circulates partially in body cavity
Basically, what you want to know is : how similar are the Species?
If you look at Species A and B - all of their enzymes are different! so they're not very similar.
Species A and C have all the same enzymes, so A and C are related and B is less related to them. Tree 2 is the correct tree.