The genetic mechanism that may have been responsible for the base sequence changes between humans and gorillas?

Which element is found in both dna and proteins

Legumes, a type of plant, require rhizobia, a type of soil bacteria, to survive since these organisms fix nitrogen during photosynthesis. rhizobia use the legumes for food. what would most likely happen to the legume population if rhizobia suddenly became extinct?

Is there any species that went extinct in recent years due to natural causes (not caused by human interaction). if so, what caused it?