The discovery of fossilised giraffe footprints next to crashing waves in the southern Cape has forced a rethink about the area’s Ice Age history.
Charles Helm and Jan de Vynck, from the Centre for Coastal Paleoscience at Nelson Mandela University in Port Elizabeth, stumbled across the tracks during a field trip, and they reveal their find in the latest issue of the South African Journal of Science.
“Until now there have been no reliable historical or skeletal fossil records for the giraffe south of the Orange River or northern Namaqualand,” said lead author Helm.Rock art records
A rock art site from the Hex River Valley included line images of at least two giraffe (shown here as tracings). According to the South African Journal of Science, the images are yellow-orange in colour and were recorded as being 170 mm in height and in poor condition. The art site also included antelope painted in finger dots.The discovery, alongside a “significant accumulation of elephant tracks” in the rocky remains of ancient dunes, meant there must have been a savanna ecosystem at the time in the floodplains of the Gouritz and Breede rivers.
Helm said he had been exploring a 275-km stretch of coastline since 2007 but came across the 12 giraffe tracks east of Still Bay only in 2016. Shifts in the rocky coastal landscape had probably only recently exposed them “nestled between a prominent cliff to the north and the Indian Ocean to the south, on a wave-cut platform”.
But they were not likely to last long, he said. “Visits in 2017 revealed interim partial degradation of the track surface caused by erosion. Given its precarious perch, the likelihood of it falling into the ocean is high.”Helm said De Vynck’s photogrammetry — the science of making measurements from photographs — would allow for the re-creation of the rocky surface. “Alternatively, the creation of a replica using latex or silicone would be feasible.”In the meantime, Helm said the discovery had “important implications for the Late Pleistocene (Ice Age) climate and vegetation of the region, since giraffes were linked to extensive sub-tropical savanna. The likely location for this ecosystem is on the broad floodplain of the southern Cape river valleys. The presence of giraffe tracks at the margin of this submerged plain is likely evidence for such vegetation.”