A treasure trove of fossils that includes dinosaur bones, bird feathers and the first presence of feathered dinosaurs beyond the southern polar circle has been discovered in Australia.
A team of researchers analyzed 10 fossil feathers found, including "tufted hair-like 'proto-feathers' from meat-eating dinosaurs, together with downy body feathers, and wing feathers from primitive birds that would have been used for flight," according to a statement accompanying the study.
"Dinosaur skeletons and even the fragile bones of early birds have been found at ancient high-latitudes before. Yet, to date, no directly attributable integumentary remains have been discovered to show that dinosaurs used feathers to survive in extreme polar habitats," said the study's lead author, Benjamin Kear, in a statement.
"These Australian fossil feathers are therefore highly significant because they came from dinosaurs and small birds that were living in a seasonally very cold environment with months of polar darkness every year," Kear added.
The fossilized feathers were discovered in the Koonwarra Fish Beds Geological Reserve and were encased in muddy sediments at the bottom of a lake.
"Fossil feathers have been known from Koonwarra since the early 1960s, and were recognized as evidence of ancient birds, but have otherwise received very little scientific attention," said Thomas Rich, of the Melbourne Museum in Australia, in the statement. "Our study is thus the first to comprehensively document these remains, which include new specimens that were examined using cutting-edge technologies."
Fossil bird expert Professor Patricia Vickers-Rich of Monash University and the Swinburne University of Technology in Australia said the feathers are "preserved in incredible detail," adding, "There are even tiny filament-like structures that would have 'zipped' the feather vanes together, just as in the flight feathers of modern birds."
Unlike feathers of modern-day birds, smaller dinosaurs had "proto-feathers," likely used to keep warm, according to experts.
"Dinosaur 'proto-feathers' would have been used for insulation," said one of the study's co-authors, Martin Kundrát. "The discovery of 'proto-feathers' at Koonwarra therefore suggests that fluffy feather coats might have helped small dinosaurs keep warm in ancient polar habitats."
The study has been published in the scientific journal Gondwana Research.