SPEAKER: Prior to the time that Charles Darwin wrote The Origin of Species in 1859, it was widely assumed that animals and plants as we see them today had not changed since the day of their creation as detailed in the Book of Genesis. That is, species were immutable.
The Swedish naturalist Carolus Linnaeus, living in the 18th century and specializing in botany, decided that it would be a good idea to organize, in some systematic way, the names of living things that were known and to include even some mythical creatures where it was a possibility that they had not yet been discovered. So beginning in the 1730s, he put together a volume called The System of Nature, which, by its 10th edition in 1758, included considerable detail about the placement of humans among the order called the primates, the order to which we now include the monkeys, the apes, and humans.
Now, we should understand that Linnaeus was not an evolutionist. He was organizing nature according to a scheme where he saw similarities between animals and plants that indicated that they were created more or less by the same design and the same [INAUDIBLE] plan or basic pattern. But there was no sense of change of species over time.
There was also, in the time of Linnaeus, considerable confusion about the apes and about other populations that, as a category, are called the monstrous races. The monstrous races were chimerae of individuals, populations, or persons that had some animal characteristics and some human characteristics, among them the so-called blemmyes. The blemmyes are the ones that had no heads, but had their eyes on their chests. There were the dog-headed people. And there were also the strap-footed people, who, in inclement weather, could raise their foot over their head and protect themselves from rain, and so on.
The ideas of these mythical creatures, which go back to Greco-Roman antiquity, were also confused with the first discoveries of the living anthropoid apes. And it was not until the 18th century that we knew about chimpanzees. And it was not until the middle of the 19th century that we had good information on gorillas.
So this confusion of monstrous races, the apes and monkeys, and diversity in human populations was a source of concern to Linnaeus in his classification in his book, The System of Nature. In fact, we see a good example of this in one of the works of his student, [INAUDIBLE] who in his doctoral dissertation in the year 1760 combined these monstrous populations with the apes in an effort to sort them out.
Since the taxonomy, or the scientific organization of living things, that was established by Linnaeus became popular, it was understood that there was an apparent gradation between the different animals. Now, we would understand much of that gradation today in terms of evolution. But the theory going on in the 18th century and up until the time that Darwin wrote The Origin-- the notion was that we had, essentially, a system of links that were very intimate between one organism and another, between one species and another. That is, there was a gradualism and a continuity so that whatever species you were looking at, there was a species immediately below it that had many of its qualities, and another species immediately above it in this hierarchy with some of its qualities, too.
This sounds evolutionary, because it means that there was transition of form. However, there was no temporal concept in this. There was no idea that there had been change over time. There was no notion that one species had converted into another.
The concept of gradation and hierarchy of all living things is derived from a very old concept called the chain of being, or the ladder of life. In fact, Aristotle talks about it. And it certainly was a very popular notion in the Middle Ages. It is the idea that there are imperceptible links between one species and another in the succession of life and that humans, of course, stand at the upper end of that range, although above humans, you would also have a hierarchy of supernatural beings-- angels, archangels, and so on.
When we began to understand more about the apes, it was not only through discovery of new apes and monkeys that we had not known about earlier, but also the advances in comparative anatomy. And here, it was possible to dissect apes and humans and see the great frequency of organic structures that they shared and where their differences were explicable in terms of their different adaptations, perhaps to locomotion, to life in the trees, life on the ground, and to many other differences that we now know distinguish the non-human primates from ourselves.
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Since the time of separation of the evolutionary lines of apes and humans about 5 million years ago, some fossil specimens of the skeletal remains of our earliest ancestors have been preserved and discovered. Putting together the pieces of the puzzle of human biological history is the task of paleontologists, geologists and anthropologists.
In this room we explore how these scientists can reconstruct the past from their studies of the geological contexts in which fossils are found, the dating of the specimens, their comparative anatomy with extinct and living species of our taxonomic order, the Primates, and the lifeways and behavior patterns of the first members of the human family within the Primates.
By looking at reproductions and pictures of this fossil record, including representations of pre-human Primate species, we learn about our prehistoric beginnings among those populations of first two million years of our evolution, as identified as Ardipithecus, Australopithecus and the earliest members assigned to our own genus- Homo habilis and Homo rudolfensis.
This video is part 6 of 13 in the Human Paleontology series.