The evolutionary effects of the genetic drift are the greatest when the population is small.
In small populations, genetic drift can significantly change the frequencies of the alleles and affect the genetic structure of the population. In big populations, the effects of the genetic drift are small and insignificant.
Answer:
The correct answer is B.
Explanation:
Option A is wrong. Mammals were not the prominent species before the extinction of dinosaurs because the mammal species that lived during the dinosaurs' era were so small that they only weighed several grams and occupied small areas as their habitats.
Option C is wrong. As dinosaurs became extinct, reptiles and "birds" remained as their descendant which evolved to some of the species that we know today.
Option D is wrong. Pangea started to break up to form the geographic isolation for the diversion of many species around 175 million years ago.
So the correct answer is B. Massive extinction disrupts and changes the food chain in such a big way that it triggers a domino effect that leads to species adapting to their new environment and diversifying thus forming new species in the process.
I hope this answer helps.
Answer:
Critical thinking requires scientists to ask questions about information they come across and assess its validity. This facet of critical thinking helps them avoid bias that originates from personal opinion and helps them distinguish information and fact from common belief.
