If you can’t wait for my analysis of the PNAS article (slated for the June 29th issue) about the giant Peruvian penguins Icadyptes salasi and the smaller Perudyptes devriesi, here’s a list of articles covering the story. While the new finds certainly have implications for the evolution of penguins, everyone is acting especially surprised that these birds lived in an area much warmer than the Antarctic, but I guess they’ve never heard of the Galapagos Penguin (Spheniscus mendiculus) or even the African (“Jackass”) Penguin (Spheniscus demersus). This reminds me that I need to pick up G.G. Simpson’s book Penguins: Past and Present, Here and There, but I’ve got lots of books to get through before I start ordering anything new. Anyway, here is the abstract and the entries relevant to the big birds;
Julia A. Clarke, Daniel T. Ksepka, Marcelo Stucchi, Mario Urbina, Norberto Giannini, Sara Bertelli, Yanina Narváez, and Clint A. Boyd (2007). “Paleogene equatorial penguins challenge the proposed relationship between penguin biogeography, body size evolution, and Cenozoic climate change.” Proceedings of the National Academy of Sciences (PNAS) June 29, 2007.
New penguin fossils from the Eocene of Peru force a reevaluation of previous hypotheses regarding the causal role of climate change in penguin evolution. Repeatedly, it was proposed that penguins originated in high southern latitudes and arrived at equatorial regions relatively recently (e.g., 4 to 8 million years ago), only well after the onset of latest Eocene/Oligocene global cooling and increases in polar ice volume. By contrast, new discoveries from the middle and late Eocene of Peru reveal that penguins invaded low latitudes over 30 million years earlier than prior data supported, during one of the warmest intervals of the Cenozoic. A diverse fauna includes two new species, here reported from two of the best exemplars of Paleogene penguins yet recovered. The most comprehensive phylogenetic analysis of Sphenisciformes to date, combining morphological and molecular data, places the new species outside the extant penguin radiation (crown clade: Spheniscidae) and supports two separate dispersals to equatorial (paleolatitude ~14� S) regions during greenhouse Earth conditions. One new species is among the deepest divergences within Sphenisciformes. The second is the most complete giant (>1.5m standing height) penguin yet described. Both species provide critical information on early penguin cranial osteology, trends in penguin body size, and the evolution of the penguin flipper.
LiveScience – Giant Ancient Penguins Liked it Hot
PhysOrg.com – Prehistoric equatorial penguins reached 5 feet in height
BBC News – Tropical giant penguin discovered
Mongabay.com – Past global warming produced monster penguins
The Guardian – Pick up a penguin? Not this one you wouldn’t
EurekAlert! – March of the giant penguins
San Francisco Chronicle – Rethinking penguins — big, warm-weather fossil