The size and types of the largest local land animals vary greatly from place to place, prompting scientists to question what controls the success of animals of certain sizes over others. Now a report published in the current issue of the Proceedings of the National Academy of Sciences shows that the size of a landmass limits the maximal body size of its top animal.
Gary Burness and Jared Diamond of the University of California School of Medicine, together with Timothy Flannery of the South Australian Museum in Adelaide, examined the body size and food requirements of top terrestrial animals from the last 65,000 years. The list included herbivores and carnivores from 25 oceanic islands and five continents, ranging from the woolly mammoth of Eurasia to the dwarf hippopotamus of Cyprus. The researchers found that the maximal body size of land animals relates to the size of the landmass on which they live: larger animals require larger individual territories to obtain sufficient food. And because more food is available to herbivores from a given area, they tend to be larger than carnivores inhabiting the same range.
According to the report, this relationship between land area and animal size is strong enough to induce evolutionary change over long time periods. The authors cite examples of animals that migrated from mainland environments to colonize an island for which they were too large and those species that grew in response to a new, relatively colossal home range. The Wrangel Island mammoth, for one, declined approximately 65 percent in body size in the 5,000 years after the severing of the land bridge linking the island to Eurasia.
Sarah Graham | Scientific American
Biologists unravel another mystery of what makes DNA go 'loopy'
16.03.2018 | Emory Health Sciences
Scientists map the portal to the cell's nucleus
16.03.2018 | Rockefeller University
Animal photoreceptors capture light with photopigments. Researchers from the University of Göttingen have now discovered that these photopigments fulfill an...
On 15 March, the AWI research aeroplane Polar 5 will depart for Greenland. Concentrating on the furthest northeast region of the island, an international team...
The world’s second-largest ice shelf was the destination for a Polarstern expedition that ended in Punta Arenas, Chile on 14th March 2018. Oceanographers from...
At the 2018 ILA Berlin Air Show from April 25–29, the Fraunhofer Institute for Laser Technology ILT is showcasing extreme high-speed Laser Material Deposition (EHLA): A video documents how for metal components that are highly loaded, EHLA has already proved itself as an alternative to hard chrome plating, which is now allowed only under special conditions.
When the EU restricted the use of hexavalent chromium compounds to special applications requiring authorization, the move prompted a rethink in the surface...
At the ILA Berlin, hall 4, booth 202, Fraunhofer FHR will present two radar sensors for navigation support of drones. The sensors are valuable components in the implementation of autonomous flying drones: they function as obstacle detectors to prevent collisions. Radar sensors also operate reliably in restricted visibility, e.g. in foggy or dusty conditions. Due to their ability to measure distances with high precision, the radar sensors can also be used as altimeters when other sources of information such as barometers or GPS are not available or cannot operate optimally.
Drones play an increasingly important role in the area of logistics and services. Well-known logistic companies place great hope in these compact, aerial...
16.03.2018 | Event News
13.03.2018 | Event News
08.03.2018 | Event News
16.03.2018 | Earth Sciences
16.03.2018 | Physics and Astronomy
16.03.2018 | Life Sciences