<span><span>a. </span>Reproducing</span>
f. obtaining
energy
d.
maintaining structure
Why do these
three illustrate the great challenge for every species.
<span><span>
1. </span>Reproduction, is as vital for an entire race to survive. It prolongs
their generation onwards and offspring to the next centuries to pass by.</span>
<span><span>
2. </span>Obtaining energy. In both humans and animals, even plants is a
challenge because these creatures need to work in order to obtain these need
resource from food –preys.</span>
<span><span>
3. </span><span>Maintaining structure. For the living organisms to still exist they
need to keep themselves intact. Combating diseases and having nutrition. This is
a by-product of having energy. </span></span>
A phylogenetic tree<span> or evolutionary </span>tree<span> is a branching diagram or "</span>tree<span>" showing the inferred evolutionary relationships among various biological species or other entities—their </span>phylogeny<span>—based upon similarities and differences in their physical or genetic characteristics.</span>
Answer:
Genetic drift
Explanation:
Genetic drift can also be referred to as allelic drift, it refers to the variation in allelic frequencies within a particular population over a period of time. It can also be referred to as the random fluctuations in the number of genotypes within a population. Genetic drift is not influenced by the environment and is usually more pronounced in a small population of organisms.
For example, a population of birds can consist of green feathers and blue feathers with the green feathers as the dominant allele, but as a result of random fluctuations, the offspring may all be with green feathers and hence could eliminate or reduce the allele responsible for blue feathers over time.