What Australopithecus sediba Ate

Already winning status in the press as the “new human species from South Africa” (a description from April 2012’s Scientific American)1 despite its controversial place in the Homo sapiens lineage even among evolutionists, two of the Australopithecus sediba fossils from Lee Berger’s South African now-famous find (see News to Note, December 31, 2011: Year in Review) have acquired acclaim for their unique diet. Analysis of phytoliths—tiny bits of plant material found fossilized in their dental calculus—suggests Au. sediba ate a variety of foods that included bark.

Similar dietary studies have been done on other fossils no longer considered in the human lineage (such as “Nutcracker man,” considered an evolutionary dead-end, and which is neither man nor a nut-cracker, see Toxin Lovers) and also on fossils of early Homo (humans). Lead author Amanda Henry and colleagues including Lee Berger report their “results from the first extraction of plant phytoliths from dental calculus of an early hominin” reveal Au. sediba’s overall diet differed from what is known of “other hominins in the region and elsewhere.”2 Promoted as the oldest known direct ancestor of Homo erectus by Berger due to some minor variations from other australopithecine apes, sediba’s reputation for uniqueness now continues through dietary analysis.

Carbon isotope analysis of plant material can help categorize the source of plant material. Most carbon in nature is carbon-12. A tiny amount is carbon-13, a non-radioactive form having one extra neutron per atom. Plants utilize carbon dioxide for photosynthesis, but the first step varies. Most plants, such as trees and shrubs, first form a three-carbon compound. Others, such as tropical grasses, start with a four-carbon compound. Plants utilizing the three-carbon approach discriminate against carbon dioxide containing carbon-13. Thus, isotopic analysis of food residue combined with the pattern of dental scratches can offer clues to diet.

Analysis of the teeth and tooth tartar in the sediba specimens suggested a diet consisting primarily of plants obtained from trees, such as fruit, leaves, and bark.

Analysis of the teeth and tooth tartar in the sediba specimens suggested a diet consisting primarily of plants obtained from trees, such as fruit, leaves, and bark. While resembling the diet of modern chimpanzees, there was more variety in that more of the grassy C-4 plants were present than normally found in chimpanzees. The latter finding is more typical of other australopith species, “Nutcracker man,” and extinct early Homo species.3 Therefore, the results are interpreted as support for Au. sediba’s intermediate oldest-human-ancestor position on the evolutionary lineage of humanity.

“There is more variety in our past than we expected,” says Henry. “We’re seeing more variation among the diets and behaviors of early hominins than we’d previously seen.”4 She says the findings suggest “there wasn’t a single, straight line from an early, primitive hominin to us. Many of our ancestors and relatives branched out, tried new things and generally worked at doing what was best in their environment at that particular time.”5 Evolutionists define hominin as members of “the lineage that includes humans and their relatives after they split from those of chimpanzees.”6

Evolutionists typically play paleo-Scrabble with data on isolated bits of fossils from fingertips to tooth tartar to support the candidacy of various fossils for prime spots on the human ancestral tree, ranking how ape-like or human-like various traits are. The recent rancor over sediba is recounted in “Sediba with a Little Sleight of Hand.” However, in truth there are apes and there are humans. There is variety among apes, and there is variety among humans, but there is no proof that humans evolved from ape-like ancestors.

Evolutionists accept as axiomatic, however, that humans must have evolved from ape-like ancestors and then examine anatomical features they interpret as intermediate to determine the lines of ancestry. Now we can add dietary features to this list of traits. Evolutionists believe the kind of food an ape-like creature consumed contributed to its capacity for cerebral evolution toward human brain status. (After all, we’ve all learned the importance of brain food!7) But nothing about an animal’s diet can provide it with the genetic information to change into a human. For all their touted similarities, which are not unexpected considering we share a Common Designer, humans and apes have enormous differences. Those differences include the physical, the genetic, the intellectual, and the spiritual.

We know from the book of Genesis that God did not use one type of organism as raw material for the next but instead spoke each kind into existence over the course of a few days. Apes and human beings were each created on the sixth day of Creation Week about 6,000 years ago. But human beings have a spiritual nature apes have never had (and will never have). Only humans were made in the image of God. As for Au. sediba, just as analysis of its fossils reveals it to be a variety of australopithecine ape, so its dietary patterns are consistent with those of apes. The only descendants of ape-like ancestors were more apes.