PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Latitude and rain dictated where species lived

Latitude and rain dictated where species lived
2011-05-13
(Press-News.org) PROVIDENCE, R.I. [Brown University] — Aggregating nearly the entire landmass of Earth, Pangaea was a continent the likes our planet has not seen for the last 200 million years. Its size meant there was a lot of space for animals to roam, for there were few geographical barriers, such as mountains or ice caps, to contain them.

Yet, strangely, animals confined themselves. Studying a transect of Pangaea stretching from about three degrees south to 26 degrees north (a long swath in the center of the continent covering tropical and semiarid temperate zones), a team of scientists led by Jessica Whiteside at Brown University has determined that reptiles, represented by a species called procolophonids, lived in one area, while mammals, represented by a precursor species called traversodont cynodonts, lived in another. Though similar in many ways, their paths evidently did not cross.

"We're answering a question that goes back to Darwin's time," said Whiteside, assistant professor of geological sciences at Brown, who studies ancient climates. "What controls where organisms live? The two main constraints are geography and climate."

Turning to climate, the frequency of rainfall along lines of latitude directly influenced where animals lived, the scientists write in a paper published this week in the online early edition of the Proceedings of the National Academy of Sciences. In the tropical zone where the mammal-relative traversodont cynodonts lived, monsoon-like rains fell twice a year. But farther north on Pangaea, in the temperate regions where the procolophonids predominated, major rains occurred only once a year. It was the difference in the precipitation, the researchers conclude, that sorted the mammals' range from that of the reptiles.

The scientists focused on an important physiological difference between the two: how they excrete. Mammals lose water when they excrete and need to replenish what they lose. Reptiles (and birds) get rid of bodily waste in the form of uric acid in a solid or semisolid form that contains very little water.

On Pangaea, the mammals needed a water-rich area, so the availability of water played a decisive role in determining where they lived. "It's interesting that something as basic as how the body deals with waste can restrict the movement of an entire group," Whiteside said.

In water-limited areas, "the reptiles had a competitive advantage over mammals," Whiteside said. She thinks the reptiles didn't migrate into the equatorial regions because they already had found their niche.

The researchers compiled a climate record for Pangaea during the late Triassic period, from 234 million years ago to 209 million years ago, using samples collected from lakes and ancient rift basins stretching from modern-day Georgia to Nova Scotia. Pangaea was a hothouse then: Temperatures were about 20 degrees Celsius hotter in the summer, and atmospheric carbon dioxide was five to 20 times greater than today. Yet there were regional differences, including rainfall amounts.

The researchers base the rainfall gap on variations in the Earth's precession, or the wobble on its axis, coupled with the eccentricity cycle, based on the Earth's orbital position to the sun. Together, these Milankovitch cycles influence how much sunlight, or energy, reaches different areas of the planet. During the late Triassic, the equatorial regions received more sunlight, thus more energy to generate more frequent rainfall. The higher latitudes, with less total sunlight, experienced less rain.

The research is important because climate change projections shows areas that would receive less precipitation, which could put mammals there under stress.

"There is evidence that climate change over the last 100 years has already changed the distribution of mammal species," said Danielle Grogan, a graduate student in Whiteside's research group. "Our study can help us predict negative climate effects on mammals in the future."



INFORMATION:

Contributing authors include Grogan, Paul Olsen from Columbia University, and Dennis Kent from Rutgers. The National Science Foundation and the Richard Salomon Foundation funded the research.

[Attachments] See images for this press release:
Latitude and rain dictated where species lived

ELSE PRESS RELEASES FROM THIS DATE:

Was Millionaire Entrepreneur Keith Middlebrook Telling the Truth About Partying With Lindsay Lohan?

Was Millionaire Entrepreneur Keith Middlebrook Telling the Truth About Partying With Lindsay Lohan?
2011-05-13
From private dinners with Paris Hilton at the Sundance Film Festival to the Men's Luxury Toy Expo, to the Muhammed Ali "Night of Champions" charity dinner, millionaire entrepreneur Keith Middlebrook has a long standing reputation for funding charity events, funding promotions, and for funding just plain fun. This includes several weekends of partying at the Chateau Marmont Hotel with Lindsay Lohan. Keith Middlebrook was recently featured on the cover of Star magazine when someone from inside the Chateau Marmont sold his American Express credit card receipts ...

African Americans and the general public support banning menthol in cigarettes

2011-05-13
According to a new study released online today, a majority of Americans, including most African Americans, stand together in support of banning menthol in cigarettes just as other cigarette flavorings have now been banned by the FDA. According to established reports, 83 percent of African American smokers and 24 percent of white smokers smoke menthol cigarettes. This new study was done by the Center for Child and Adolescent Health Policy at MassGeneral Hospital for Children (MGHfC), the American Academy of Pediatrics' Julius B. Richmond Center of Excellence, and the ...

Mixing fluids efficiently in confined spaces: Let the fingers do the working

2011-05-13
Getting two fluids to mix in small or confined spaces is a big problem in many industries where, for instance, the introduction of one fluid can help extract another — like water pumped underground can release oil trapped in porous rock — or where the mixing of liquids is the essential point of the process. A key example of the latter is microfluidics technology, which allows for the controlled manipulation of fluids in miniscule channels often only a few hundred nanometers wide. Microfluidic devices were first introduced in the 1980s and for many years were best known ...

NREL's multi-junction solar cells teach scientists how to turn plants into powerhouses

2011-05-13
Plants can overcome their evolutionary legacies to become much better at using biological photosynthesis to produce energy, the kind of energy that can power vehicles in the near future, an all-star collection of biologists, physicists, photochemists, and solar scientists has found. A U.S. Department of Energy (DOE) workshop that drew a prestigious collection of 18 scientists to compare the efficiency of plants and photovoltaic solar cells led to an important and provocative scholarly article in today's issue of the journal Science. Two of the scientists are from DOE's ...

Risking one's neck for better grog: Mutinies reveal tipping points for collective unrest

Risking ones neck for better grog: Mutinies reveal tipping points for collective unrest
2011-05-13
Films depicting the 1787 mutiny aboard the British ship HMS Bounty show sailors living cheek by jowl, being forced to dance, enduring storm-ridden Cape of Good Hope crossings to satisfy the ship captain's ego and being flogged for trivial reasons. We may not think that these harsh conditions have much relevance today. But mutinies continue to occur, especially in the armed forces of developing nations. And mutinies have similarities to other types of rebellions, including worker strikes, riots, prison rebellions and political uprisings. University of Washington sociologists ...

Solar cells more efficient than photosynthesis -- for now

2011-05-13
EAST LANSING, Mich. — In a head-to-head battle of harvesting the sun's energy, solar cells beat plants, according to a new paper in Science. But scientists think they can even up the playing field, says researcher David Kramer at Michigan State University. Plants are less efficient at capturing the energy in sunlight than solar cells mostly because they have too much evolutionary baggage. Plants have to power a living thing, whereas solar cells only have to send electricity down a wire. This is a big difference because if photosynthesis makes a mistake, it makes toxic ...

Diagnosing 'seizures' in the US economy

Diagnosing seizures in the US economy
2011-05-13
Since 2008, the U.S. economy has been "seizing" uncontrollably. Now a Tel Aviv University researcher says that a comparison of the multifaceted economic downturn with the uncontrolled spasms of an epileptic is not inappropriate — and may say something about the origins of the disaster. In a recent article published in the journal PLoS ONE, Prof. Eshel Ben-Jacob of Tel Aviv University's School of Physics and Astronomy, his doctoral student Dror Y. Kenett and economist Dr. Gitit Gur-Gershgorn examined the dynamics of the S&P 500 over the last decade, employing methods originally ...

Wildlife Conservation Society recommends health measures for Argentina's caiman ranches

Wildlife Conservation Society recommends health measures for Argentinas caiman ranches
2011-05-13
The Wildlife Conservation Society and other organizations released a new study recommending a disease screening program for farm-raised caiman in ranching facilities in Argentina to ensure the safety of people and wildlife alike. The recommendations focus on two crocodilian species, the yacare caiman and broad-snouted caiman, both of which are reared in caiman ranches for sustainable harvest. The research team sought to assess the presence of potentially harmful bacteria in captive-raised caiman at a typical ranching facility in Argentina's Chaco region, where several ...

Vidaroo Contracts with Emmis Radio for Expanded Use of its Video Platform

2011-05-13
Vidaroo Corporation today announced that it has contracted with Emmis Radio, a subsidiary of Emmis Communications Corporation, for use of its video distribution and syndication platform for Emmis' 22 radio stations. Vidaroo's Enterprise software will allow Emmis' radio stations to deliver its website's video distribution through use of Vidaroo's centralized management platform, as well as distribute live and on-demand content and branded time-of-day programming. In addition to use of the Vidaroo platform for video distribution and syndication, Emmis will also be able ...

AGU Journal highlights -- May 12, 2011

2011-05-13
The following highlights summarize research papers that have been recently published in Geophysical Research Letters (GRL), Water Resources Research (WRR), the Journal of Geophysical Research-Oceans (JGR-C), and the Journal of Geophysical Research-Solid Earth (JGR-B). In this release: New freshwater source for Antarctic coastal waters Phytoplankton affect clouds and precipitation River model enhanced by floodplain dynamics Weighing natural variability in projected precipitation change Study suggests no slowing of Atlantic 'conveyor belt' current Warming, salinity ...

LAST 30 PRESS RELEASES:

Call for papers: 14th Asia-Pacific Conference on Transportation and the Environment (APTE 2025)

A novel disturbance rejection optimal guidance method for enhancing precision landing performance of reusable rockets

New scan method unveils lung function secrets

Searching for hidden medieval stories from the island of the Sagas

Breakthrough study reveals bumetanide treatment restores early social communication in fragile X syndrome mouse model

Neuroscience leader reveals oxytocin's crucial role beyond the 'love hormone' label

Twelve questions to ask your doctor for better brain health in the new year

Microelectronics Science Research Centers to lead charge on next-generation designs and prototypes

Study identifies genetic cause for yellow nail syndrome

New drug to prevent migraine may start working right away

Good news for people with MS: COVID-19 infection not tied to worsening symptoms

Department of Energy announces $179 million for Microelectronics Science Research Centers

Human-related activities continue to threaten global climate and productivity

Public shows greater acceptance of RSV vaccine as vaccine hesitancy appears to have plateaued

Unraveling the power and influence of language

Gene editing tool reduces Alzheimer’s plaque precursor in mice

TNF inhibitors prevent complications in kids with Crohn's disease, recommended as first-line therapies

Twisted Edison: Bright, elliptically polarized incandescent light

Structural cell protein also directly regulates gene transcription

Breaking boundaries: Researchers isolate quantum coherence in classical light systems

Brain map clarifies neuronal connectivity behind motor function

Researchers find compromised indoor air in homes following Marshall Fire

Months after Colorado's Marshall Fire, residents of surviving homes reported health symptoms, poor air quality

Identification of chemical constituents and blood-absorbed components of Shenqi Fuzheng extract based on UPLC-triple-TOF/MS technology

'Glass fences' hinder Japanese female faculty in international research, study finds

Vector winds forecast by numerical weather prediction models still in need of optimization

New research identifies key cellular mechanism driving Alzheimer’s disease

Trends in buprenorphine dispensing among adolescents and young adults in the US

Emergency department physicians vary widely in their likelihood of hospitalizing a patient, even within the same facility

Firearm and motor vehicle pediatric deaths— intersections of age, sex, race, and ethnicity

[Press-News.org] Latitude and rain dictated where species lived