The discovery by two local fossil hunters on a river bank in Victoria has ‘potentially far-reaching implications’, scientists say

Fossilised claw prints found in Australia suggest amniotes – the ancestors of reptiles, birds and mammals – evolved about 40m years earlier than thought.

The footprints, in sandstone dated 354m to 358m years old, were probably made by reptiles crossing a surface dimpled by raindrops. Researchers said the trackways represent the oldest evidence of amniotes on the planet.

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Karenia mikimotoi algae can suffocate fish, cause haemorrhaging and act as a neurotoxin, one expert says

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More than 200 marine species, including deepwater sharks, leafy sea dragons and octopuses, have been killed by a toxic algal bloom that has been affecting South Australia’s coastline since March.

Nearly half (47%) of the dead species were ray-finned fish and a quarter (26%) were sharks and rays, according to OzFish analysis of 1,400 citizen scientist reports.

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The state government is aware of koala welfare problems but says it has ‘no cost-effective’ solutions

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Thousands of koalas are being displaced each year as blue gum plantations are cut down in Victoria, worsening overcrowding in nearby forests and exacerbating the risk of injury and death during bushfires.

An estimated 42,500 koalas live in blue gum plantations in south-west Victoria, data shows. Between 8,000 and 10,000 hectares of plantation are harvested each year, making thousands of koalas homeless.

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