Kangaroo evolution linked to climatic change

Aug 04, 2010
Kangaroo evolution linked to climatic change

(PhysOrg.com) -- The evolution of kangaroos is intricately tied to Australia's changing climate, according to new research.

In the first anatomical study of the entire skeletons of both modern and species, Flinders University palaeontologist Dr Gavin Prideaux and Murdoch University anatomist Dr Natalie Warburton have pieced together the most reliable and detailed family tree to date.

Their findings, published this month in the Zoological Journal of the Linnean Society, show how the abundance and diversity of macropods - including kangaroos, wallabies and tree-kangaroos - matches the spread of woodlands and grasslands in Australia as forests retreated to the coast over millions of years.

“Kangaroos and wallabies have long been recognised as potentially ideal barometers of historical climatic change in Australia,” Dr Prideaux said.

“They have been around for at least 30 million years, but difficulties in working out which species are related and when certain lineages evolved have hampered research for more than a century,” he said.

By comparing skeletons from 35 living and extinct macropod species, the researchers established that while early forms were adapted to the abundant soft-leaved forest plants, but later macropods had to adapt to more arid conditions.

“We see clear changes through time in teeth and skull shape that reflect diets of tough leaves and grasses, and parallel changes in foot anatomy that reflect an improved ability to hop longer distances through more open habitats,” he said.

The scientists argue that the Macropus lineage, which contains the red and grey kangaroos and some wallabies, represents the peak of marsupial evolution.

“Macropus has been around for four million years and has more living and than any other marsupial genus. They are a great Australian success story,” Dr Prideaux said.

The study also confirms previous about the relationships of the highly endangered merrnine, a small wallaby restricted to two tiny Western Australian islands.

“The merrnine is the sole living survivor of a unique branch of the macropod evolutionary tree that split off around 20 million years ago, but we know very little about the animal. While its conservation is a priority, studies of its biology should teach us a lot about the formative steps in macropod evolution,” Dr Prideaux said.

Explore further: 'Killer sperm' prevents mating between worm species

Provided by Flinders University

3.3 /5 (9 votes)

Related Stories

Global warming threatens Australia's iconic kangaroos

Oct 15, 2008

As concerns about the effects of global warming continue to mount, a new study published in the December issue of Physiological and Biochemical Zoology finds that an increase in average temperature of only two degrees Celsiu ...

Lessons learned from drought deaths 40,000 years ago

Nov 27, 2006

Drought-stricken Australia should heed a warning from a new study that shows a series of massive droughts killed giant kangaroos and other "megafauna" in south-east Queensland 40,000 years ago, according to ...

Loud and lazy but didn't chew gum: Ancient koalas

Dec 19, 2009

(PhysOrg.com) -- Skull fragments of prehistoric koalas from the Riversleigh rainforests of millions of year ago suggest they shared the modern koala's "lazy" lifestyle and ability to produce loud "bellowing" ...

Recommended for you

'Killer sperm' prevents mating between worm species

17 hours ago

The classic definition of a biological species is the ability to breed within its group, and the inability to breed outside it. For instance, breeding a horse and a donkey may result in a live mule offspring, ...

Rare Sri Lankan leopards born in French zoo

20 hours ago

Two rare Sri Lankan leopard cubs have been born in a zoo in northern France, a boost for a sub-species that numbers only about 700 in the wild, the head of the facility said Tuesday.

Researcher reveals how amphibians crossed continents

22 hours ago

There are more than 7,000 known species of amphibians that can be found in nearly every type of ecosystem on six continents. But there have been few attempts to understand exactly when and how frogs, toads, ...

User comments : 0