We were not always the earth's sole hominid. Neanderthals (and Denisovans, and Homo floresiensis (if they were truly distinct species) overlapped our time. Here are two skeletons, one of ours and one of theirs.
The first Neanderthals appeared perhaps a quarter of a million years ago and certainly by 170,000 years BP. They seem to have supplanted Homo heidlebergensis, a more distant cousin of ours, and they flourished from Spain to Israel, as far north as Finland, and possibly as far east as the Altai mountains in Siberia. In order to live in cold climates, they would have clothed themselves, though of course not a trace of a garment has survived. Neanderthals, it's been newly determined, carried a gene associated with pale skin and red hair. Their brain cases were slightly larger than ours, but shaped differently -- bulging at the sides and protruding in the back. Their rib cases flared at the bottom and their pelvises were broad, which meant that their strides necessarily involved a lot more hip rotation than our straightforward gait. They were more robust than we, with heavier bones and muscles, and they were much stronger. They ate more than we did and matured more rapidly -- their wisdom teeth developed at six years of age. Earlier Neanderthal populations appear to have been scavengers, but later ones were predators, capable of taking mammoths and wooly rhinoceroses. The plaque of Neanderthal teeth reveal traces of phytoliths which occur in the roots and leaves of plants. It's known that they ate dates, barley and legumes. Both meat and plants were cooked. There is some fragmentary evidence that they practiced cannibalism, but, I'd prefer to think, only "survival cannibalism." Neanderthals lived in bands or perhaps 8 or 10 members. They occasionally buried their dead, but left behind no evidence of ritual or ceremony. They knapped chert and flint into scrapers and hand axes and the knew how to bind stone to wooden handles with adhesives and sinew, but they did not make use of bone tools.
They were gone from the earth about 20,000 years ago, displaced by homines sapientes and perhaps reduced by changes in the climate or by other destructive natural events.
Humans of European origin (but not of African or Asian) interbred with Neanderthals, so that as much of 4% of human DNA is Neanderthal. On ther other hand, no Homo sapiens DNA has been discovered in Neanderthal populations. No one knows why the one and not the other.
This report is filched from Ian Tattersall's Masters of the Planet (2012), an excellent book that brought me up to date on human origins. I recommend it with genuine enthusiasm. It's learned, clearly written, and sensible. And it displaces the cartoon history I grew up with in which monkeys lead to apes and then to Piltdown (!!!) man and then to insurance salesmen in tie and jacket. The modern picture is more complicated and far more fascinating and also replete with unsolved puzzles.