These are the faces of our ancestors, the ancient hominid cousins of humanity. Before us, there was them. They weren't quite human, but they were so like us.
Sahelanthropus tchadensis: 6.8 million years ago
Australopithecus afarensis: 3.2 million years ago
Australopithecus africanus: 2.5 million years ago
Paranthropus aethiopicus: 2.5 million years ago
Paranthropus boisei: 1.8 million years ago
Homo rudolfensis: 1.8 million years ago
Homo ergaster: 1.3 million years ago
Homo heidelbergensis: 500,000 years ago
Homo neanderthalensis: 600,000 to 350,000 years ago
Homo floresiensis (The Hobbit): 30,000 years ago
And the only hominid not gone extinct (at least not yet), Homo sapiens: 200,000 years ago
Haha, I was gonna say "No way I'm related to Rudolph!". But yeah, it could explain a few neighbors.
I recognize at least one that we've interbred with. (No kidding.) I guess Denisovans are another (race?) I'm thinking of. I could look it up, but no time today.
I expect that they are not 'dead', but became neighbors!
It is just that 'burial' rights or rituals became part of culture fairly recently. Before this, their remains dropped where where they died....
Over time genetic drift, specialization, issolation, in-breeding, etc finished the job.
We are all descended from Africans.
Why is there such a pronounced change in the structure of the nose between homo rudolfensis and homo ergaster? It's a huge change in my eye.
Anyone notice the uncanny resemblance of Vladimir Putin to a couple of them?
I was able to shut down a creationist rant one time by listing just SOME of these names. The person went on a tirade about Piltdown man (a rather infamous deliberate fraud) and tried to claim that proved the whole thing about human descent from (other) apes was just a big lie, and I ran off just some of these names (as well as some others that we now know aren't really distinct species, see below) as well-attested examples of predecessor species and they actually STFU. I didn't convince them (I am sure) but fence sitters probably learned to have a little more respect for our side of this "debate."
A cautionary note. It's possible that some of these casts were made from a very atypical example of the species that just happened to be the one we've been lucky enough to find a fossil of. At least one of the casts also display noticeable asymmetry which implies either the fossil was damaged after death, or the individual suffered some sort of injury during their life. Or that the lighting is playing tricks on me.
There was a recently announced discovery at a site (Dmanesi) of a fairly large number of skeletons. They displayed enough variation that it looked like a bunch of previously-recognized species (ergaster, heidelbergensis, rudolfensis, and even habilis) were living together. The obvious conclusion is that what they thought were different species (before) are in fact just examples of a lot of physical variation within a species (or even within a subspecies). A lot of paleoanthropologists had suspected that this was the case for quite some time (there is after all a huge incentive to declare you've found a new species, rather than just an outlier of one that already is recognized) so I will bet they feel pretty vindicated right about now. In any case if this finding is excepted a lot of "Homo" species will be merged into (probably) ergaster.
Imagine if you will Pat Robertson's and Patrick Stewart's skulls being the only two examples of Homo sapiens to survive as skulls; they would look very different (Robertson has a high forehead and Stewart does not). Throw in skulls from other parts of the world where bone structure is also different and you might end up with five or six recognized "species"--especially since they could argue that the people they dug up in China were a different population from the people in Southern Africa with no possibility of interbreeding over that vast difference. (That reasoning will hold until they find traces of an airliner. Unlikely since I doubt aluminum would last that long.)
And yes I am completely unable to explain why Robertson's forehead is so high given the evident lack of content therein.
Bible study has hollowed out the thinking regions of Robertson's skull.
I've mostly been hearing about this verbally (the whole human evolution subject is a hobby of a friend of mine, so he keeps me posted; the disadvantage being what I repeat ends up being hearsay). But a fairly quick Google gives me this:
I skimmed it and it seems to be highlighting the issue. Anyhow, it in turn points to this:
http://www.sciencemag.org/content/342/6156/326.abstract which is a little more of a primary source.
And yes your point about science also discovering and correcting the frauds but not being given credit for that is a solid one.
When I took my year of anthropology, early 80's, I was a little concerned about 'sampling'. Now it appears the epigenetic effects might also be very important. I recently watched a documentary that mentioned possible environmental causing birth defects even in rather 'natural' contexts.