2014 GSA Annual Meeting in Vancouver, British Columbia (19–22 October 2014) Paper No. 134-14

Presentation Time: 9:00 AM-6:30 PM

TRACKING EXTINCT GIANTS: PEDOBAROMETRY AND DISCOVERY POTENTIAL OF THE LARGEST LAND MAMMAL (INDRICOTHERIINAE) AND HISTORIC BIRD (AEPYORNITHIDAE) FOOTPRINTS

BUYNEVICH, Ilya V., Earth and Environmental Science, Temple University, Philadelphia, PA 19122, [email protected]

To date, no conclusive evidence exists of the footprints of the largest terrestrial mammal (Oligocene indricotheriine rhinoceros) and historic ratite (elephant bird, Aepyornis sp.). Based on their paleoecology and allometry, the potential for track discovery can be assessed by addressing the filtering effects of formation- preservation-recognition biases. For indricotheres, the lack of ichnological record is due to hard-packed nature of contemporary semi-arid scrubland substrates, limited accessibility to productive Eurasian sites, and finds of skeletal remains in coarse-grained fluvial strata. Favoring track preservation are wide home/migration ranges and presence of fine-grained and lime-rich facies in fluvio-deltaic/lacustrine areas and watering holes. Based on fleshed limb dimensions of these perissodactyls, their tridactyl prints should be at least 50-60 cm in width. Scaling to elephant and rhinoceros pedobarometry (mass ~ juvenile indricotheres), digitiportal Paraceratherium sp. males with a conservative maximum weight of 15 tonnes likely exerted mid-stance foot pressures of ~200 kPa (edge loading ~1,500 kPa). For aepyornithids, the isolation of Madagascar and the focus on extracting skeletons and eggs from swamplands were not conducive to ichnological research. Abundant eggshell fields in coastal dunefields, likely concentrated as deflation lag of nesting sites, may provide useful information on aeolian paleo-surfaces traversed by the ratites. Their true tracks are likely to be larger than moa’s (>30 cm wide) and morphologically similar to some ornithopod dinosaurs. For adults weighing 0.3-0.4 tonnes, dynamic foot pressures may have been as high as 70-80 kPa (edge loading ~300 kPa). Once paleo-surfaces at indricothere and elephant bird localities are constrained, search for naturally weathered traces can be complemented with high-frequency georadar (>500 MHz GPR) imaging for identifying traces and undertracks, especially in sand-rich hyporelief. Efforts focused on mapping tracking surfaces, combined with GPR imaging of mammoth tracks and neoichnological experiments with modern megafaunal locomotion in varying substrates, should eventually lead to trackway discoveries, shedding light on the distribution, geomorphic impact, speed, and behavior of these extinct giants.

2014 GSA Annual Meeting in Vancouver, British Columbia (19–22 October 2014) General Information for this Meeting

Session No. 134--Booth# 252 Topics in Paleoecology: Modern Analogues and Ancient Systems (Posters) Vancouver Convention Center-West: Exhibition Hall C 9:00 AM-6:30 PM, Monday, 20 October 2014

A large and flightless bird found in the North Atlantic and as far south as Northern Spain. It had an average height of 75-85 cm and weighed about 5kg. The Great Auk was a powerful swimmer which helped it to hunt underwater for food. An extinct flightless bird that inhabited Mauritius, the Dodo was about one metre tall and may have weighed 10–18 kg. The only account we have of the Dodo’s appearance is through varied illustrations and written accounts from the 17th century so its exact appearance remains unresolved. An enormous mammal, believed to be closely related to the modern-day elephant. Its ancestors migrated out of Africa about 3.5 million years ago, spreading across northern Eurasia and North America. Results Only six continental birds and three continental mammals were recorded in standard databases as going extinct since 1500 compared to 123 bird species and 58 mammal species on islands. Of the extinctions, 95% were on islands. On a per unit area basis, the extinction rate on islands was 177 times higher for mammals and 187 times higher for birds than on continents. The continental mammal extinction rate was between 0.89 and 7.4 times the background rate, whereas the island mammal extinction rate was between 82 and 702 times background. One of the largest land mammals of all time was Paraceratherium. Cimolestids (Cimolesta)[edit]. The largest-known Old World monkey is the prehistoric baboon, with a male specimen of Dinopithecus projected to weigh an average of 46 kg (101 lb) and up to 57 kg (125 lb).[42] It exceeds the maximum weight record of the chacma baboon, the largest extant baboon. Before the discovery of Josephoartigasia monesi, another giant rodent was known, Phoberomys insolita, but it was known from only a few fragments, so its real size is unknown.[citation needed] A slightly smaller relative, Phoberomys pattersoni, was found, which was 3 m (9.8 ft) long and weighed 320 kg (700 lb).[citation needed]. Massive Large Bodied Mammal Die Offs of the Pleistocene. Share. Flipboard. A replica statue of the extinct Mylodon ground sloth which inhabited the south of the Chilean and Argentinian Patagonia, inside a cave in the Torres del Paine national park which was home to the pre- historic creature. Germán Vogel / Getty Images. Twenty or more genera of giant marsupials, monotremes, birds, and reptiles were likely wiped out due to the direct intervention of human populations since they can find no connection to climate change. The local decline in diversity began nearly 75,000 years before human colonization, and thus cannot be the result of human intervention.