Claim CC220:
Arthropods arose suddenly in the fossil record. There are no
transitionals leading up to them.
Response:
- Anomalocaris, from the Cambrian and Precambrian, has a pair of
segmented appendages, indicating arthropod affinities, but it also
seems to have lobopod legs. The related Opabinia also apparently
had
lobopod legs. Other rare Cambrian and Precambrian fossils show some
promise of shedding more light on relationships. For example,
Spriggina, another Precambrian animal, has a head shield similar to
trilobites (Conway Morris 1998, 184-185).
Links:
Morton, Glenn R. 2000. Phylum level evolution.
http://home.entouch.net/dmd/cambevol.htm
References:
- Conway Morris, Simon. 1998. The Crucible of Creation, Oxford
University Press.
created 2003-6-23
