The Science of Being Human

But evolution is not a process of increasing complexity, nor any other measure of superiority you can find.

Our genus Homo contains just one species at the moment, and that’s us

none of us is an island and we all live out our lives surrounded by other humans.

and to my mind there is nothing more fascinating than the science of being human.

he system was invented back in 1735 by one of the great scientists of the eighteenth century, a Swedish naturalist called Carl Linnaeus

the humble and dull-looking lymphocytes turned out to be at the heart of the system. Not only that, there are three distinct flavours of lymphocyte: the B-cells make antibodies, the T-cells identify foreign agents in our bodies and the natural killer cells seek out and destroy our own cells that have become infected with viruses.

After this we get to members of our own Homo genus, in turn: Homo habilis, Homo erectus, Homo neanderthalensis and, finally, Homo sapiens

the figure next to the ape is an Australopithecus of some sort

But if organism B can also breed with organism C, then that makes all three organisms the same species, except that in a ring species organism C can’t breed with organism A, which means they are different species

If organism A can breed with organism B, even if they look different, then according to some biological species concepts they are the same species.