What evidence does the discovery of tiktaalik give to support the theory of evolution? A- tiktaalik shows that land animals and fish are not as closely related as once thought
B- tiktaalik shows that land animals and fish developed from completely different ancestors
C- tiktaalik shows that fish decided to grow legs at some point which allowed him to walk on land
D-tiktaalik shows extinct extinct species are related to modern species, supports the idea of common ancestry

humans can cause extinction of a species through overharvesting, pollution, habitat destruction, introduction of invasive species (such as new predators and food competitors), overhunting, and other influences. explosive, unsustainable human population growth is an essential cause of the extinction crisis.

explanation:

i didn't have the answer choices , but i tried my best.

a tetrad is the foursome during meiosis made by two homologous chromosomes that have each already replicated into a pair of sister chromatids.

helicase, i think thats it