Humans are ground-dwelling terrestrial primates who first evolved from chimpanzees millions of years ago via natural selection of random mutations that rendered the offspring humans and their descendants unable to survive in the tree environment for which their parents, ancestors, and non-mutated siblings were well-adapted. But the fortuitous genetic changes serendipitously also made the newly evolved humans better able to live in a ground environment that was unsuitable for their arboreal ancestors.

Missing evolutionary links among the earliest humans are extremely difficult to locate because comparatively few are present in the fossil record. They evidently were intelligent enough to avoid terrestrial "death traps" (quicksand, tarpits, collapsed cave-roofs, floods, landslides, volcanic ash eruptions) that buried and preserved less advanced and less alert species. In addition, there were fewer numbers of the first humans compared with the expanded populations of later ones.

DNA analysis indicates that humans evolved from our closest relatives, chimpanzees. Radioactive Argon40 measurements date the earliest known humans, Ar. (Ardipithecus) ramidus, as having lived about 4.4 mya (million years ago). Decades before Ar. ramidus fossils were discovered, Au.(Australopithicus) afarensis fossils, who had lived ~3.6 mya, were considered to have been the earliest humans. During those decades, a missing link between Au. afarensis and our ancestral chimpanzees was sought. Ar. ramidus turned out to be that evolutionary connecting link. (An older 6.0 myr hominid, Orrorin tugonensis, may not have been in the lineage that led to Homo sapiens.) [Note: ~ means approximately]

Now, another important transitional human fossil link has been found. This latest confirmation of Darwin's seminal theory of evolution hammers yet another nail into the coffin of false creationism and intelligent design concepts --- particularly since it solely involves humans. The new link is Au. anamensis which evolved and lived ~4.1 mya. This establishes Au. anamensis chronologically between Au. afarensis (~3.6 mya) and Ar. ramidus (4.4 mya). There are innumeral quintillions of different species that have lived on Earth since the first organisms evolved ~3.8 billion years ago. Many of them became fossils, but not all will ever be found, because many of them have been destroyed by erosion.

Geologists and paleontologists will continue to search for, dig up, study, and learn from as many fossils as possible. Those that have been analyzed to date indicate consistently that evolution was involved in their formation. It is almost certain that all future organisms and fossils will continue to substantiate the validity of Darwin's theory of evolution.

Filling evolutionary gaps in the fossil record of aquatic invertebrates is usually easy because there have been so many more invertebrates than vertebrates --- and there are astronomically greater numbers of aquatic fossils than terrestrial ones. Land areas typically are erosional environments where rocks and sediments containing fossils are often destroyed by erosion, or transported by running water down to lakes and oceans, whose quiet waters constitute depositional environments where chances of organisms being buried and preserved are infinitely better than for terrestrial ones.

Au. anemensis is but the latest of myriad ancestral human and other missing links that have been discovered. Paleontologists and biologists recognize that evolution is the mechanism, which has created the diversity of life that existed on Earth in the past and in the present. Chance mutations among descendent generations produce new species that differ from their parental stock.

Interestingly, gardeners, vintners and farmers constantly (and often unwittingly) verify evolution when they select plants with desired characteristics that they want to reproduce in future generations in order to create new genetic lines. This might be called gardener, or vintner, or farmer selection --- whereas when it occurs in Nature via evolution, it's called natural selection.