The 'cheek' is the common name for the insect GENA.
The gena is located in the head area of insects. The gena forms the sclerotized area on each side of the head, below the compound eyes, which extends to the gular structure. The gena varies among species of insects.
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.
Fossils are found of giraffes with short necks.
Lamarck believed the giraffes stretched their necks and passed it to their offspring
necks grew longer due to stretching.
giraffes need long necks for food and evolution provided it to them
