You're not that different from a mouse. Or a fruit fly. Or even a lancelet. These were the great discoveries of biology in the 20th century, which saw the alignment of some of the ultimate ideas in the history of ideas. Evolution by natural selection was resolved with the nature of inheritance via genetics. And then came the revelation that DNA is universal in living things we share the same code and, in many cases, the same genes with distant evolutionary cousins. Science is always subject to change and to continuous self-revision. But I'm willing to stick my neck out and assert that these ideas are here to stay and will never be fundamentally overturned.
Most elegantly they combined in the 1990s, when the emerging field of developmental genetics how DNA shapes our bodies teamed up with evolutionary biology to form the gestalt field known as "evo-devo". We saw that the same genes did very similar things in wildly different species. We did freakish experiments that revealed deeply rooted common ancestry. We saw that the body plans of the most starkly different shaped animals were in fact very similar if you looked hard enough. My personal favourite is the embryological gene I worked on called Pax6, whose role is to decree where an eye is going to be, in all species that have eyes. Astonishingly and brilliantly researchers took Pax6 from a mouse, and stuck it in a fruit fly whose own Pax6 was broken. Lo and behold, the fly's error was corrected and it grew eyes. Fly eyes, not mouse eyes.
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