Saturday, June 30, 2012

[Paleontology • 2012] New Avian tracks from the lower to middle Eocene at Fossil Hill, King George Island, Antarctica

A flightless bird of the Phorusrhacidae family that lived in Antarctica 48 million years ago, on King George Island, the largest of the South Shetland Islands in Antarctica [Credit: Huffington Post International]

Trace fossils are long known to exist in the Fossil Hill Formation (lower to middle Eocene) at Fildes Peninsula, King George Island, Antarctica. During fieldwork in 2009, abundant new avian tracks were recovered, which are analysed here. Three avian ichnotaxa are distinguished. The most common impressions are tridactyls and tetradactyls with slender digit imprints II–IV and a posterior hallux. They are included in the ichnogenus Gruipeda. In addition tridactyl and tetradactyl footprints with short and thick digit impressions are conferred to Uhangrichnus. The third ichnotaxon is a tridactyl impression with broad and short digits assigned to Avipeda. The latter taxon is here documented for the first time from Antarctica. These avian tracks are preserved in volcaniclastic sediments consisting in reddish-brown layers of mudstone intercalated with coarse sandstone. The sequence represents lacustrine environments which seasonally dried and were episodically refilled. 
Key words: avian footprints; Cenozoic; Gondwana; ichnotaxonomy

The fossilized bird tracks at King George Island [Credit: Huffington Post International]

Chilean scientist discovers fossil Antarctic bird prints

2012. New Avian tracks from the lower to middle Eocene at Fossil Hill, King George Island, Antarctica. Antarctic Science. DOI: