Systematics and Evolution
Some studies published on the phylogeny of the petrels suggests that the diving petrels are actually members of the family Procellariidae, and some taxonomic works treat them as such.
The four species are:
- Peruvian Diving Petrel Pelecanoides garnotii
- Magellanic Diving Petrel Pelecanoides magellani
- South Georgia Diving Petrel Pelecanoides georgicus
- Common Diving Petrel Pelecanoides urinatrix
The evolution and systematics of these birds is not well researched. Several populations were described as distinct species and while most of them are only subspecies, some may indeed be distinct. The prehistoric fossil record was long limited to very fragmentary remains described as P. cymatotrypetes found in Early Pliocene deposits of Langebaanweg, South Africa; while this bird apparently was close to the Common Diving Petrel, no members of the genus are known from South African waters today.
In 2007, a humerus piece from New Zealand was described as P. miokuaka. This was found in Early/Middle Miocene deposits and just as may be expected, it far more resembles diving petrels than any other known bird, but presents a less apomorphic condition.
Read more about this topic: Diving Petrel
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