There are several species that have remained fairly similar for huge amounts of time. Sharks and alligators for instance though there are also many insects too.
Sharks are the most successful. They evolved before there was any life on land. They evolved 200 million years befor the dinosaurs and crocodiles. They evolved 150 million years before insects. They are the only animal that have reached the end of evolution and have stopped evolving. They evolved in the late Ordivician period and became sharks we know in the Silurain period, 400 million years ago. They are the perfect predator.
They dont
Most animals aren't. It is believed that the animals painted on cave walls were painted there as part of rituals intended to secure a successful hunt, or to celebrate successful hunts.
Dolphins .
The Animals
The rhinoceros, especially the black rhinoceros, is one of the most engangered animals on earth.
Insects
Homosexual behavior has been observed in most animals on earth.
Phylum Athropoda, ( The Arthropods) as they contain the insects of which there are 800 000 species and the insects are the most abundant animals on earth.
vertebrates
Technically, humans.
No it is not
Insects