Recent work by two researchers from University College London (UCL) and George Washington University (GW) calls into serious question the capability of paleoanthropologists to detect and establish the evolutionary relationships assumed to exist among bipedal primates, or hominids.
Evolutionary or phylogenetic relationships for the hominids are determined by comparing anatomical features of specimens found in the fossil record with those of extant species.1
For the hominids, the available fossils in most cases are partial crania, partial jaw bones, isolated teeth, and infrequently, partial upper and lower limbs.2-3 Rarely do paleoanthropologists find a complete cranium, let alone a nearly complete skeleton. And only a few of the hominid species in the fossil record are known from an abundance of specimens. Typically a hominid species is defined by just a few fossilized bone fragments.4 Many times the hominid remains have been crushed, shattered and damaged prior to fossilization or have become deformed as a result of geological processes. This only serves to compound the difficulty of paleoanthropologists’ work.
Given the nature of the hominid fossil record, it is not surprising that most evolutionary biologists recognize that the best they can hope for are crude working phylogenies.5 (A phylogeny is believed to be the evolutionary pathway for an organism or group of organisms.) This becomes apparent when one examines textbooks and treatises on human evolution. The large number of proposed phylogenies shows that paleoanthropologists are far from a consensus on the pathway to human evolution.6-7
The situation has recently worsened for those attempting to construct hominid phylogenetic relationships. Scientists from UCL and GW indicate, based on their findings, that evolutionary phylogenies postulated for human origins are hopelessly uncertain.8 These two paleoanthropologists compared phylogenies constructed from gene and protein sequences with those constructed from cranial and dental features for two currently existing groups of primates, the hominoids (gorillas, chimpanzees, and humans) and the papionins (baboons, mangabeys, and macaques).
In both cases, the molecular phylogenies differed significantly from those derived using cranial and dental characteristics. Since evolutionary biologists consider molecular phylogenies inherently more robust, the authors of the study are forced to conclude that craniodental characteristics cannot be used as reliable indicators of primate evolutionary relationships (including those of extinct hominids). As the researchers from UCL and GW put it, “Without a reliable phylogeny, little confidence can be placed in the hypotheses of ancestry…”9
In light of these results, the assertion that human evolution is a fact becomes scientifically untenable. What seems apparent is that evolutionary biologists have chosen to interpret their data exclusively within an evolutionary paradigm. From this framework, they then declare that their data supports human evolution. To demonstrate that humans evolved by natural processes, there must be rigorous evidence of clearly established evolutionary relationships with obvious transitions in the fossil record. This study shows that such determinations may never be possible, given that cranial and dental remains are the primary fossils available to paleoanthropologists.
Equally disconcerting for the evolutionary paradigm is the lack of congruence between molecular and morphological phylogenies. Truth demands internal consistency. The failure to establish consistency for molecular and morphological phylogenies calls into question the veracity of the evolutionary paradigm.
New discoveries in paleoanthropology increasingly undermine the plausibility of evolution as an explanation for human origins.