Recently discovered skull material belonging to the extinct koalas Litokoala and Nimiokoala offers a major step forward in understanding koala evolution, according to a new study published in the Journal of Vertebrate Paleontology. The study, which was carried out by a team led by Dr. Julien Louys of the University of New South Wales in Sydney, Australia, focused on the evolution of the masticatory (chewing) apparatus and hearing.
At the time these extinct koalas lived, the Australian continent was wetter and much more forested than it is today. As the continent dried out and the flora became dominated by plants with hard, tough leaves, animals such as koalas had to adapt to this new food resource. The team led by Dr. Louys found that the chewing apparatus of the living koala is much more specialized than its fossil forebears, including adaptations for more powerful bite forces and the ability to shred the tough leaves of the eucalypts that are the mainstay of its diet.
In contrast, analysis of the middle ear suggests that differences between the fossil and living koalas are relatively small. This indicates that the specialized loud and complex vocalizations of living koalas – a trait unusual among marsupials – likely have an ancient origin. The study therefore shows that the chewing apparatus and hearing adaptations in living koalas evolved at different times and under different environmental circumstances, an indication that adaptations, even in the most specialized animals, may have disparate origins and evolve in mosaic fashion.
Reference: Louys et al.: Cranial anatomy of Oligo-Miocene koalas (Diprotodontia: Phascolarctidae): stages in the evolution of an extreme leaf-eating specialization.
Journal Web site: Society of Vertebrate Paleontology: http://www.vertpaleo.org
| Newswise Science News
Interfacial engineering core@shell nanoparticles for active and selective direct H2O2 generation
19.09.2018 | Science China Press
Making better use of enzymes: a new research project at Jacobs University
19.09.2018 | Jacobs University Bremen gGmbH
Thin-film solar cells made of crystalline silicon are inexpensive and achieve efficiencies of a good 14 percent. However, they could do even better if their shiny surfaces reflected less light. A team led by Prof. Christiane Becker from the Helmholtz-Zentrum Berlin (HZB) has now patented a sophisticated new solution to this problem.
"It is not enough simply to bring more light into the cell," says Christiane Becker. Such surface structures can even ultimately reduce the efficiency by...
A study in the journal Bulletin of Marine Science describes a new, blood-red species of octocoral found in Panama. The species in the genus Thesea was discovered in the threatened low-light reef environment on Hannibal Bank, 60 kilometers off mainland Pacific Panama, by researchers at the Smithsonian Tropical Research Institute in Panama (STRI) and the Centro de Investigación en Ciencias del Mar y Limnología (CIMAR) at the University of Costa Rica.
Scientists established the new species, Thesea dalioi, by comparing its physical traits, such as branch thickness and the bright red colony color, with the...
Scientists have succeeded in observing the first long-distance transfer of information in a magnetic group of materials known as antiferromagnets.
An international team of researchers has mapped Nemo's genome, providing the research community with an invaluable resource to decode the response of fish to...
Graphene is considered a promising candidate for the nanoelectronics of the future. In theory, it should allow clock rates up to a thousand times faster than today’s silicon-based electronics. Scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) and the University of Duisburg-Essen (UDE), in cooperation with the Max Planck Institute for Polymer Research (MPI-P), have now shown for the first time that graphene can actually convert electronic signals with frequencies in the gigahertz range – which correspond to today’s clock rates – extremely efficiently into signals with several times higher frequency. The researchers present their results in the scientific journal “Nature”.
Graphene – an ultrathin material consisting of a single layer of interlinked carbon atoms – is considered a promising candidate for the nanoelectronics of the...
03.09.2018 | Event News
27.08.2018 | Event News
17.08.2018 | Event News
19.09.2018 | Life Sciences
19.09.2018 | Physics and Astronomy
19.09.2018 | Information Technology