New rat genus discovered in the birthplace of the theory of evolution

New rat genus

2013-09-20

(Press-News.org) A prominent tuft of spiny hair on the back, a white tail tip and three pairs of teats represent the unique set of characteristics describing a new genus of rat which has been discovered in the Moluccan province of Indonesia. This region had a profound influence on the British Naturalist Alfred Russell Wallace who independently developed the theory of evolution alongside Charles Darwin. The international team of zoologists was led by the Museum Zoologicum Bogoriense in Indonesia and the Center for Macroecology, Evolution and Climate at the University of Copenhagen.

One hundred years after the death of Sir Alfred Russel Wallace, an international team of zoologists has discovered a new genus of mammal in the Halmahera Island in Indonesia. It is located in Wallacea, an Eastern Indonesian region named after the British Naturalist himself. The team was surprised to find the new endemic rodent close to the locality of Boki Mekot, a mountainous area under severe ecological threat due to mining and deforestation.

Drawing: Jon Fjelså

The species is only known in this locality and is named Halmaheramys bokimekot. Project leader Pierre-Henri Fabre from the Center for Macroecology, Evolution and Climate states:

"This new rodent highlights the large amount of unknown biodiversity in this Wallacean region and the importance of its conservation. It constitutes a valuable addition to our knowledge of the Wallacean biodiversity and much remains to be learned about mammalian biodiversity across this region. Zoologists must continue to explore this area in order to discover and describe new species in this highly diverse, but also threatened region."

Halmaheramys bokimekot is a terrestrial spiny rat of medium body size with brownish grey fur on its back and a greyish white belly. Together with its other characteristics it represents a unique set of features that has never been reported before in the Moluccas.

The region that inspired Wallace

It is clear that the region had a profound influence of Wallace's thinking as it was from the Moluccan province of Indonesia that Wallace wrote his famous letter about natural selection and evolutionary theory to Charles Darwin. The two naturalists both published their findings in 1858.

The unique nature of the plants and animals found within the region and the large floral and faunal differences to the neighboring region of Australia, later inspired Wallace to define a zoogeographical boundary dividing the Indonesian archipelago into two distinct parts: a western portion in which the animals are largely of Asian origin and an eastern portion where the fauna reflect Australasia. This is known as the Wallace line.

New rat reveals a rare migration event

"The Halmaheramys discovery supports Wallace's idea of an important faunal breakup in this region. Most of the species on the island of Halmahera reflect eastern origins, but our genetic analysis revealed a western origin of the new rat genus. That reflects the unique transition zone found in the Indo-Pacific, and warrants much greater scientific investigation," says Pierre-Henri Fabre.

Photo: Pierre-Henri Fabre. The picture represents the colonisation road of native rat lineages in the Wallacean region. The map also illustrates the Indo-Malay travel of AR Wallace.

Last year he and colleagues from the Center for Macroecology, Evolution and Climate provided an update of Wallace's zoogeographical world map from 1876 based on modern technology such as DNA analysis and hundreds of thousands of species records. The study showed that in spite of lacking modern techniques Wallace's zoogeographical boundaries of the world were remarkably accurately.

"Such a remarkable island setting inspired one of the greatest biologists of all time, and if Sir Alfred Russell Wallace were alive today he would surely be excited by the prospect of further conservation and biodiversity study within the Moluccas," says Pierre-Henri Fabre.

Photo: Pierre Henri Fabre

###

The team's findings are published in the Zoological Journal of the Linnean society:

Fabre P.-H.*, Pagès M., Musser G.G., Fitriana Y.S., Fjeldså J., Jennings A., Jønsson K.A., Kennedy J., Michaux J., Semiadi G., Supriatna N., & Helgen K. (early view) A new genus of rodent from the Wallacea (Rodentia: Muridae: Murinae: Rattini) and its implication for biogeography and Indo-Pacific Rattini systematics. Zoological Journal of the Linnean Society, Vol.169(2).

Contact

Project leader Pierre-Henri Fabre, phone: +33 626242375, skype: pierrehenrifabre

Communications Officer Elisabeth Wulffeld, Center for Macroecology, Evolution and Climate, mobile: +45 21179140

ELSE PRESS RELEASES FROM THIS DATE:

Getting rid of unwanted visitors

2013-09-20

The digestive systems of all animals contain a large number of different bacteria. Humans are no exception and our intestines provide warmth, shelter and food to a vast range of unicellular organisms, many of which are either beneficial to their hosts or at least cause no ill effects other than consuming some of the food we ingest. However, several species have been associated with disease. Among them is Helicobacter pylori, which may play a part in causing chronic gastritis and gastric ulcers. An ancient colonizer recently discovered Helicobacter pylori was only discovered ...

Crucial new insight into the secrets of Nobel Prize-winning pump

2013-09-20

The story of the sodium-potassium pump has strong ties to Denmark. In 1997, the Danish scientist Jens Chr. Skou received the Nobel Prize in Chemistry for his discovery, and over the years, research on the pump has remained a strong focus area at Aarhus University. In 2007, the joint efforts of various research teams at Aarhus University led to the description of the structure of the potassium-bound state of the pump - now, Danish researchers have also described the other state of the pump; the sodium-bound state. The results were recently published in the journal Science. The ...

New research on inherited herpesvirus may have implications for transplantation

2013-09-20

Up to half a million people in Britain today may not know it, but in their genetic material they carry a particular form of herpesvirus 6 inherited from a parent. The study from the world-renowned Department of Genetics at the University of Leicester, is funded principally by the Medical Research Council (MRC), and published in the journal Nucleic Acids Research. The research led by Dr Nicola Royle, Senior Lecturer in Genetics, has identified a mechanism by which the inherited herpesvirus 6 can escape from the chromosome and may be able to reactivate under certain ...

Elvitegravir fixed combination in HIV: Lesser benefit for treatment-naive patients

2013-09-20

The drug combination of elvitegravir, cobicistat, emtricitabine and tenofovir disoproxil (elvitegravir fixed combination, trade name: Stribild) has been approved in Germany since May 2013 for the treatment of adults infected with human immunodeficiency virus type 1 (HIV-1). In an early benefit assessment pursuant to the Act on the Reform of the Market for Medicinal Products (AMNOG), the German Institute for Quality and Efficiency in Health Care (IQWiG) examined whether an added benefit is proven for this combination over the current standard therapy. This is not the case: ...

Blood pressure cuff may save lives in patients with acute heart attack

2013-09-20

In patients with an acute heart attack, remote ischemic conditioning – intermittent inflation of a blood pressure cuff to cut off blood flow to the arm during transportation to hospital for acute balloon dilatation – reduces subsequent cardiac symptoms and mortality after acute heart attack. The results are presented by researchers from Aarhus University Hospital and Aarhus University in European Heart Journal on-line 12 September 2013. Activating the body's defense mechanism Lack of oxygen for short periods of time in a distant organ by intermittently stopping blood ...

Promising new alloy for resistive switching memory

2013-09-20

WASHINGTON, D.C. Sept. 20, 2013 -- Memory based on electrically-induced "resistive switching" effects have generated a great deal of interest among engineers searching for faster and smaller devices because resistive switching would allow for a higher memory density. Researchers have tested a number of oxide materials for their promise in resistive switching memories, and now a team of researchers in Singapore have demonstrated how conductive nano-filaments in amorphous titanium dioxide (TiO2) thin films could be utilized for resistive switching device applications. Yuanmin ...

Densest array of carbon nanotubes grown to date

2013-09-20

WASHINGTON, D.C. Sept. 20, 2013 -- Carbon nanotubes' outstanding mechanical, electrical and thermal properties make them an alluring material to electronics manufacturers. However, until recently scientists believed that growing the high density of tiny graphene cylinders needed for many microelectronics applications would be difficult. Now a team from Cambridge University in England has devised a simple technique to increase the density of nanotube forests grown on conductive supports about five times over previous methods. The high density nanotubes might one day replace ...

Microfluidic platform gives a clear look at a crucial step in cancer metastasis

2013-09-20

CAMBRIDGE, Mass-- Cancer cells metastasize in several stages -- first by invading surrounding tissue, then by infiltrating and spreading via the circulatory system. Some circulating cells work their way out of the vascular network, eventually forming a secondary tumor. While the initial process by which cancer cells enter the bloodstream -- called intravasation -- is well characterized, how cells escape blood vessels to permeate other tissues and organs is less clear. This process, called extravasation, is a crucial step in cancer metastasis. Now researchers at MIT ...

Personality a key factor in health care use

2013-09-20

Psychiatrists and psychologists have long understood that an individual's personality can define how he or she views the world around them, reacts to situations, and interacts with others. It now appears that personality traits can be linked to the frequency with which older adults use expensive health care services. A study, published today in the journal The Milbank Quarterly, finds that certain measurable personality characteristics can be correlated to health care consumption, in some instances increasing use high cost health care services such as emergency room ...

3 new species of tiny frogs from the remarkable region of Papua New Guinea

2013-09-20

Three new species of tiny frogs from Papua New Guinea are described in the latest issue of Zookeys. Dr Fred Kraus, University of Michigan, who in 2011 in Zookeys described the world's smallest frogs Paedophryne dekot and Paedophryne verrucosa, now adds another 3 species from the genus Oreophryne to the remarkable diversity of this region. The three new species Oreophryne cameroni, Oreophryne parkopanorum and Oreophryne gagneorum are all rather minute, with total body lengths of around 20 mm. These tiny frogs, however are still substantially larger than the species that ...

Scientists uncover the first clear evidence of air sacs in the fossilized bones of alvarezsaurian dinosaurs: the "hollow bones" which help modern day birds to fly

Alcohol makes male flies sexy

TB patients globally often incur "catastrophic costs" of up to $11,329 USD, despite many countries offering free treatment, with predominant drivers of cost being hospitalization and loss of income

New rat genus discovered in the birthplace of the theory of evolution

ELSE PRESS RELEASES FROM THIS DATE:

LAST 30 PRESS RELEASES: