Amber fossils a first for Australia
Huge chunks of amber containing the remnants of ancient rainforests have been found along beaches in Far North Queensland, the first amber fossils to be found in Australia.
The amber pieces, some as big as a football, contain flies, beetles, spiders, flowers, fungi, moss, fern spores and pollen as well as bubbles of gas and water from the time, the researchers say.
The fossils are at least 4 million years old, they say, possibly much older.
Fisherman Dale Wicks and partner Beth Norris discovered the amber while taking evening walks along the beach on the Cape York Peninsula, says University of New South Wales palaeontologist Henk Godthelp.
"It turns out that it was the very first discovery of true amber in Australia," says Godthelp, who was invited to analyse the fossils and reported the find at the Riversleigh Society meeting in Sydney this week.
While amber-like substances such as copal and coal resin are found in Australia, no-one had found true amber, he says.
Godthelp, who studies the evolution of rainforests, says the fossilised resin is most likely from kauri pine, which grows in rainforests.
He says amber is very good at preserving living creatures trapped inside it because it stops the air from getting to them and also contains chemicals that act as preservatives.
Anything trapped inside it, he says, will give a unique picture of ancient rainforests.
This includes insects, which come from the rainforest canopy, and bubbles of water or gas, which he says could provide clues about past climates.
Nearly one in five of the amber pieces found contain fossils or bubbles of water or gas, says Godthelp.
"By world standards, that's remarkably high."
Godthelp says he doesn't know how old the amber is yet but it would be at least 4 million years old, possibly much older.
"We think it's probably Tertiary," he says.
Godthelp says it is difficult to date amber directly and the researchers are searching for the original rock deposits that would have contained the amber to date it.
He says the 60-odd kilograms of amber collected so far over three years would have been washed up on beaches from elsewhere on the coast.
Based on the distribution of the amber along the Cape York beaches, and an analysis of the currents along the coast, Godthelp says it probably came from an area 200 kilometres away.
He says the team wants to protect the exact location of the amber discovery as the researchers don't want to get a rush of people looking for it and threatening a precious scientific resource.
"What we want to do is to understand the fossils in the amber rather than just have a piece of amber that's a pretty object," he says.
The research team includes scientists from the Australian Museum in Sydney.