Question

Some organisms seem to have undergone very little evolutionary change
over huge spans of geologic time. One example is the shark. Shark
ancestry dates back around 425 million years, which is about 200 million
years before the earliest known dinosaur. In all, abut 2000 to 3000
species of fossil sharks have been documented. About 1100 species of
shark remain on Earth today. These sharks represent an ancient life form.
Why do you think the rate of evolution of the shark has been so gradual?
4 sentence

Are the finches that Charles Darwin studied on the Galápagos Islands an example of divergent evolution or convergent evolution? Give two point to explain your thinking.

Answer 1

Answer:

shark are slow evolving species because of lower gene flow and rate if reproduction.

Darwin finches undergo divergent evolution

Explanation:

Sharks have evolved slowly because of following reasons –  

a) Lower rate of reproduction  

b) Restricted gene flow because of isolated habitat such as stretches of deep water

c) Staying close to the eggs and hence guarding them throughout their life thereby allowing no cross mating.  

d) Lower  rate of mitochondrial DNA (mtDNA) evolution  

Darwin’s finches show divergent evolution as different species of finches originated from a common ancestors. The beak size of finches vary form one species to other because of different diet habits