Question

scientists compile many pieces of evidence to infer evolutionary relationships. here is one such piece of evidence.
the gene bdnf encodes a protein, brain - derived neurotrophic factor, that is involved in the growth and maintenance of nerve cells in the brain and spinal cord. this table shows the number of nucleotides in bdnf that are identical between three different aquatic vertebrates: blue whales, coelacanths (a type of lobe - finned fish), and asian bonytongue fish.
the number of identical nucleotides in bdnf between pairs of aquatic vertebrates
coelacanths and asian bonytongue fish: 445
blue whales and coelacanths: 626
asian bonytongue fish and blue whales: 468
how does this evidence support the claim that coelacanths are more closely related to blue whales than to asian bonytongue fish? complete the paragraph.
coelacanths and blue whales have dropdown similarities in their bdnf nucleotide sequences than coelacanths and asian bonytongue fish have. this suggests that coelacanths and dropdown have less similar dna and evolved from a more dropdown common ancestor.

Explanation:

1. First, compare the number of identical nucleotides: Coelacanths & blue whales have 626, Coelacanths & Asian bonytongue fish have 445. So 626 > 445, meaning coelacanths and blue whales have more similarities.
2. Less similar DNA would be between coelacanths and Asian bonytongue fish (since their BDNF nucleotide matches are fewer).
3. Fewer similarities imply a more distant common ancestor (because closer relatives share more genetic material).

Answer:

First blank: more
Second blank: Asian bonytongue fish
Third blank: distant