Gorongosa 2024-FULL-FINAL - Flipbook - Page 76
PA LEO NTO LO GY
EARLY BITES Jaw fossils
from an ancient tiger shark (top)
and hyrax (bottom), a distant
relative of elephants, uncovered in
Gorongosa, reveal that part of the
landlocked park was once coastal,
which suggests our primate
forbears may have moved inland
from the coast.
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GORONGOSA SP ECIAL
Carvalho and Bobe’s hyrax specimen was found among what Carvalho
described as a “bone bed”—a layer of fossils so plentiful that the species
found within it must have died at the same time as the result of some
catastrophic occurrence. Think Pompeii or the extinction of the dinosaurs.
What local Armageddon befell the organisms on this stratum of the
Mazamba Formation remains unknown—Carvalho speculates that it could
have been a recurring flood or other major storm—but it was the bone bed
that proved Carvalho and Bobe were onto something.
On the basis of their finds at the Mazamba Formation, Carvalho and
Bobe led a study for a paper published earlier this year asserting that
the part of Gorongosa where their excavation is taking place was once
coastal. The site now sits on dry land more than 50 miles due west of the
Mozambique Strait—the waterline redrawn by ancient climatic shifts.
“This is the story of a coastal site, not an inland one, which has been the
predominant focus of African paleoanthropology,” says Carvalho. “These are
species that lived along the way between sea and land, and everything we are
finding in Gorongosa is completely different from what you would find up
north on the Rift or in the caves in South Africa—this area was an estuary.”
The discovery of this liminal space between land and
sea is an important one that has until now evaded paleontologists working in Africa, Carvalho tells me. An
understanding of where ocean and land once met is critical to discerning the footprints of our primate forbears.
“It’s in this coastal forest that you are going to find
what people have long been looking for but that no one
has found yet,” Carvalho tells me. “Our hominin
ancestors would have moved inland from here.”
Carvalho posits that during the twilight
years of the Miocene, these ancestors
might have followed riverbeds toward
the interior of the continent, the humid
rainforest vegetation along the way
shepherding them toward new environments—and new adaptations.
The spectacular discoveries of Australopithecus skeletons in the 20th century—which put
East Africa on the map as humanity’s Garden of
Eden—would seem to support this hypothesis,
says Carvalho. Lucy, perhaps the most famous
such specimen, was found in the savannas of Northeastern Ethiopia, part of the
northerly reaches of the Rift, and well
inland from the Red Sea.
At a mere 3.2 million years old, Lucy
is much younger than the apes’ teeth
that have turned up in Carvalho’s
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