The recent discovery of a Tasmanian tiger's tooth in central Queensland could mean the animal survived on mainland Australia longer than previously thought.

Palaeontologist Rochelle Lawrence, from the Capricorn Caves, said it was the second thylacine tooth to be found at the Capricorn Caves near Rockhampton, with the most recent discovery taking place last year.

She said the tooth was yet to be dated, but the find was a coup for her and fellow Queensland Museum palaeontologist Scott Hocknull.

"We need to have the deposits dated to know exactly how old that is but it could tell us that maybe they survived a little bit longer in this region," she said.

Ms Lawrence said fossils that had been discovered in the Harp Chamber from 2012 also revealed startling information on climate change.

"We actually find creatures from an ancient rainforest that was here about 500,000 years ago," she said.

One of the last images of a Tasmanian tiger, taken in captivity.. ( ABC TV )

"I first pulled out a tooth from a rainforest bandicoot and that's how we first found the rainforest species here."

She said it was a big surprise.

But the discovery of another chamber nearby, has provided a second and totally different area of study for researchers.

"The false floor we call it — if you were to shine your torch down onto that floor, you would see hundreds of thousands of fossils embedded in that floor," she said.

But unlike the rainforest, the species in this chamber came from an arid environment.

"Our fossil species is showing a change in environment through time," she said.

Ancient wonder: One of the fossil deposits at the Capricorn Caves. ( Supplied: Capricorn Caves )

"It was a big surprise — we didn't know it was there. People have been walking over it for so long."

She said there was still a lot of work to do and they were only just scratching the surface.

"The rainforest came first — 500,000 years ago we had rainforest stretching all the way up from the Caves region through northern Queensland and into the lowland forest of Papua New Guinea," she said.

The Capricorn Caves house a significant fossil deposit. ( Supplied: Capricorn Caves )

"And then something happened to the environment, a change happened, and we see these arid-adapted species coming in and taking over those rainforest species.

"Around 280,000 years ago, we find the rainforests slowly retracting, becoming isolated, and we don't see those species ever again.

"The rainforest you see in Papua New Guinea today, are the refugium of those ancient rainforests that we had in Queensland."

Megafauna species include giant possums, goannas

Ms Lawrence said the Caves contained megafauna species, including giant goannas, crocodiles, a giant snake the size of an anaconda and giant possums.

She said Naracoorte, another cave deposit in South Australia, showed different environmental changes and provided a good comparative study.

"The Cave deposits are very significant — it's showing us how climate has changed through time and that's without any human influence," she said.

Palaeontologist Rochelle Lawrence next to a dig pit in the Colosseum Chamber. ( ABC Capricornia: Inga Stünzner )

"So we have species that are going extinct, just from climate change.

"When we come to Colosseum Chamber, which is dated from 50,000 years ago to modern day. We have seen lots of species becoming extinct since European arrival in Australia.

"That's when we see a lot of species becoming extinct."