Archaehierax sylvestris. Credit: Jacob Blokland
63 bone fossil finding in desert is among the “best preserved” eagles ever and an extremely unusual discovery.
A 25- million-year-old eagle fossil discovered in South Australia contributes to the long evolutionary history of raptors in Australia.
Paleontologists from Flinders University have actually uncovered Australia’s earliest eagle fossils on a remote wilderness livestock station, explaining a brand-new fossil types which lived throughout the lateOligocene Named Archaehierax sylvestris, this types is among the earliest eagle-like raptors worldwide.
A contrast of the ready fossil tarsometatarsus (foot bone) and a hypothesised shape of Archaehierax sylvestris (left) compared to the wedge-tailed eagle Aquila audax (right). The scale bar is 10 mm long. Credit: Jacob Blokland
“This species was slightly smaller and leaner than the wedge-tailed eagle, but it’s the largest eagle known from this time period in Australia,” states Flinders University PhD prospect Ellen Mather, very first author in the brand-new paper released in the peer-reviewed journal Historical Biology
“The foot period was almost 15 cm long, which would have enabled it to understand big victim. The biggest marsupial predators at the time had to do with the size of a lap dog or big feline, so Archaehierax was definitely ruling the roost.”
“With eagles at the top of the food chain, they are always few in number — and so are infrequently preserved as fossils,” states co-author Associate Professor Trevor Worthy.
“It’s rare to find even one bone from a fossil eagle. To have most of the skeleton is pretty exciting, especially considering how old it is.”
The Australian environment throughout the Oligocene was really various to today.
The stays of Archaehierax were discovered on the barren coast of a dry lake (referred to as Lake Pinpa) in a desolate sandy desert environment throughout continuous Flinders University examinations into a lost environment, when Australia’s interior was covered in trees and verdant forests.
However, living in forests offers some difficulties for an animal that flies. So how did Archaehierax prevent accidents with trees and branches while it hunted?
“The fossil bones expose that the wings of Archaehierax (pron. ah-kay-hi-rax) were brief for its size, similar to types of forest-dwelling eagles today. Its legs, on the other hand, were reasonably long and would have offered it substantial reach,” statesMs Mather.
“The mix of these characteristics recommend Archaehierax was a nimble however not especially quick flier and was probably an ambush hunter. It was among the leading terrestrial predators of the late Oligocene, diving upon birds and mammals that lived at the time.”
Archaehierax would have hunted koalas, possums, and other animals in trees surrounding a huge shallow lake, on which waterfowl, cormorants and flamingoes were plentiful.
Palaeontologists from Flinders University excavating fossils near Lake Pinpa, SouthAustralia L to R: Aaron Camens, Amy Tschirn, Jacob Blokland and KailahThorn Credit: Trevor Worthy, Flinders University
Out of all the types understood from this website, Archaehierax is among the very best maintained; the partial fossil skeleton is consisted of 63 bones.
“I have studied this system for many years now, and this is the most exquisite fossil we have found to date,” states Associate Professor Trevor Worthy.
“The efficiency of the Archaehierax skeleton enabled us to figure out where it fits on the eagle ancestral tree. It reveals a series of functions unlike any seen amongst modern-day hawks and eagles,”Ms Mather discusses.
“We discovered that Archaehierax didn’t come from any of the living genera or households. It appears to have actually been its own distinct branch of the eagle household,” she states.
“It’s unlikely to be a direct ancestor to any species alive today.”
Reference: “An exceptional partial skeleton of a new basal raptor (Aves: Accipitridae) from the late Oligocene Namba Formation, South Australia” 27 September 2021, Historical Biology
DOI: 10.1080/0891296320211966777
