Where were you on September 1, 2005? Perhaps you missed the announcement of a scientific breakthrough: the influential journal Nature published the completed sequence of the chimpanzee genome.1
This remarkable achievement received abundant publicity because it paved the way for biologists to conduct detailed genetic comparisons between humans and chimpanzees.2
Unfortunately, the fanfare surrounding the chimpanzee genome overshadowed a more significant discovery. In the same issue, Nature published a report describing the first-ever chimpanzee fossils. This long-awaited scientific advance barely received notice because of the fascination with the chimpanzee genome. News of the two discoveries produced different reactions among scientists. Evolutionary biologists declared the chimpanzee genome as evidence for human evolution, but some paleoanthropologists were left wondering how humans and chimps could have evolved, based on where the chimpanzee fossils were found.
According to the evolutionary paradigm, humans and chimpanzees share a common ancestor. About 5 million years ago, this ancestral primate spawned two evolutionary lineages that led to humans and chimpanzees. Anthropologists consider the physical, geographical separation of hominids and proto-chimpanzees to be the "driving force" for the evolution of humans and chimpanzees. They postulate that the formation of the Rift Valley isolated the hominids in East Africa (a hot, dry savannah) from chimpanzees in Central and West Africa (with warm, wet jungles). The geographical isolation of hominids and chimps, presumably, sent these two lineages along different evolutionary trajectories.
Evolutionary biologists think that fossil hominids like "Lucy," Homo erectus, and Neanderthals document the emergence of humans.4 Yet, until recently paleoanthropologists had no corresponding fossils for the chimpanzee lineage.
Surprisingly, the first chimpanzee fossils were discovered not in West or Central Africa, but in East Africa, near Lake Baringo, Kenya. These fossils, consisting of three teeth, dated to 500,000 years in age--meaning that chimpanzees coexisted alongside hominids. The Rift Valley provided no geographical rift for separate evolutionary histories, and therefore foils a key prediction of the human evolutionary paradigm.
Sally McBrearty, one of the paleoanthropologists who uncovered the chimpanzee fossils, noted, "This means we need a better explanation of why and how chimps and humans went their separate evolutionary ways. The discovery that chimps were living in semi-arid conditions as well as in the jungles seems to blow apart the simplistic idea that it was the shift to the savannah that led to humans walking upright."5
If the discovery blows apart a "simplistic idea," maybe it's time for a simple (and testable) idea--the RTB creation model for human origins.
- The Chimpanzee Sequencing and Analysis Consortium, "Initial Sequence of the Chimpanzee Genome and Comparison with the Human Genome," Nature 437 (2005): 69-87.
- See Fazale Rana with Hugh Ross, Who Was Adam? A Creation Model Approach to the Origin of Man (Colorado Springs, CO: NavPress, 2005) for a discussion of human-chimpanzee genetic comparisons from a creation perspective.
- Sally McBrearty and Nina G. Jablonski, "First Fossil Chimpanzee," Nature 437 (2005): 105-08.
- See Who Was Adam? for a treatment on how the hominid fossil record creates problems for human evolution.
- Michael Hopkin, "First Chimp Fossil Unearthed," (August 31, 2005), http://www.nature.com/news/2005/050829/pf/050829-10_pf.html, accessed November 30, 2005.