Which animal is the largest living land animal?

The African bush elephant, up to about seven tonnes. Almost everything unusual about it follows from being that size, starting with the trunk: at that height it cannot reach the ground with its mouth, so it has a nose with something like 40,000 muscle units in it, capable of uprooting a tree or picking up a single seed.

Heat is the constant problem, because volume grows faster than surface area and a large animal struggles to shed it. The ears are the answer - thin sheets webbed with blood vessels, flapped to move air across them, cooling blood by several degrees before it returns to the body. Asian elephants, in shadier forest, have noticeably smaller ones.

They also live in societies that turn on memory. Herds are led by the oldest female, and experiments played recorded calls of strangers to herds: those with older matriarchs reacted appropriately and those with younger ones did not, because knowing which voices are dangerous takes decades to learn. The same applies to where water is in a drought. Killing the oldest animal destroys information the herd cannot rebuild, which is one reason poaching damages a population well beyond the number of animals taken.