Claim CC050:
All hominid fossils are fully human or fully ape.
Response:
- There is a fine transition between modern humans and australopithecines
and other hominids. The transition is gradual enough that it is not
clear where to draw the line between human and not.
Intermediate fossils include
- Australopithecus afarensis, from 3.9 to 3.0 million years ago (Mya).
Its skull is similar to a chimpanzee's, but with more humanlike
teeth. Most (possibly all) creationists would call this an ape, but
it was bipedal.
- Australopithecus africanus (3 to 2 Mya); its brain size, 420-500
cc, was slightly larger than A. afarensis, and its teeth yet more
humanlike.
- Homo habilis (2.4 to 1.5 Mya), which is similar to
australopithecines, but which used tools and had a larger brain
(650-cc average) and less projecting face.
- Homo erectus (1.8 to 0.3 Mya); brain size averaged about 900 cc in
early H. erectus and 1,100 cc in later ones. (Modern human
brains
average 1,350 cc.)
- A Pleistocene Homo sapiens which was "morphologically and
chronologically intermediate between archaic African fossils and
later anatomically modern Late Pleistocene humans" (White et
al. 2003, 742).
- A hominid combining features of, and possibly ancestral to,
Neanderthals and modern humans (Bermudez de Castro et al. 1997).
And there are fossils intermediate between these (Foley 1996-2004).
- Creationists themselves disagree about which intermediate hominids are
human and which are ape (Foley 2002).
- There is abundant genetic evidence for the relatedness between humans
and other apes:
- Humans have twenty-three chromosome pairs; apes have twenty-four.
Twenty-two of the pairs are similar between humans and apes. The
remaining two ape chromosomes appear to have joined; they are
similar to each half of the remaining human chromosome (chromosome
2; Yunis and Prakash 1982).
- The ends of chromosomes have repetitious telomeric sequences and a
distinctive pretelomeric region. Such sequences are found in the
middle of human chromosome 2, just as one would expect if two
chromosomes joined (IJdo et al. 1991).
- A centromere-like region of human chromosome 2 corresponds with the
centromere of the ape chromosome (Avarello et al. 1992).
- Humans and chimpanzees have innumerable sequence similarities,
including shared pseudogenes such as genetic material from ERVs
(endogenous retroviruses; Taylor 2003; Max 2003).
Links:
Foley, Jim. 1996-2004. Fossil hominids: The evidence for human evolution.
http://www.talkorigins.org/faqs/homs/
Drews, Carl, 2002. Transitional fossils of hominid skulls.
http://www.theistic-evolution.com/transitional.html
References:
- Avarello, R., A. Pedicini, A. Caiulo, O. Zuffardi, M. Fraccaro, 1992.
Evidence for an ancestral alphoid domain on the long arm of human
chromosome 2. Hum Genet 89(2): 247-249.
- Bermudez de Castro, J. M. et al., 1997. A hominid from the Lower
Pleistocene of Atapuerca, Spain: Possible ancestor to Neandertals and
modern humans. Science 276: 1392-1395.
- Foley, Jim, 1996-2003. (see above)
- Foley, Jim, 2002. Comparison of all skulls,
http://www.talkorigins.org/faqs/homs/compare.html
- IJdo, J. W., A. Baldini, D. C. Ward, S. T. Reeders and R. A. Wells,
1991. Origin of human chromosome 2: an ancestral telomere-telomere
fusion. Proceedings of the National Academy of Science USA 88(20):
9051-9055.
http://www.pnas.org/cgi/reprint/88/20/9051.pdf
- Max, Edward E., 2003. Plagiarized errors and molecular genetics.
http://www.talkorigins.org/faqs/molgen/
- Taylor, D. M. 2003. Alignment of Chimp_rp43-42n4 against human
chromosome 15. http://www-personal.umich.edu/~lilyth/erv/
See also
Taylor, D. M. 2003 (Jun 3). Re: Evolutionary Misconceptions on
Evolution.
http://www.google.com/groups?as_umsgid=75200cbc.0306031846.50b2bda5%40posting.google.com
- White, Tim D. et al., 2003. Pleistocene Homo sapiens from Middle
Awash, Ethiopia. Nature 423: 742-747.
- Yunis, J. J. and O. Prakash, 1982. The origin of man: a chromosomal
pictorial legacy. Science 215: 1525-1530.
Further Reading:
Johanson, D. C., and B. Edgar, 1996. From Lucy to Language. New York:
Simon and Schuster.
Leakey, M. and A. Walker, 1997. Early hominid fossils from
Africa. Scientific American 276(6) (June): 74-79.
Tattersall, Ian, 1995. The Fossil Trail. New York: Oxford.
created 2003-6-4, modified 2004-9-30