A gene exploits a rival gene's excesses sabotaging any sperm that bear a rival's chromosome.
--so that maturing sperm that bear chromosomes with the susceptible allele (call that one a) end up defective and discarded.
Similar selfish systems occur in mammals including humans. In the Genetics study conducted at Brown University scientists uncover new clues about how the SD gene might be gaming the system against a. It's a plot
#Monopoly of the male orangutan: Comparative field observations on Sumatra and Borneothe sexual development mating habits and social hierarchy of the orangutans are more heavily dependent on their environment than had previously been assumed:
where the rain forest supplies more food the influence of the dominant male increases. In order to escape his attention many other males remain small.
In Malay the word orangutan means man of the woods. In fact however these rain forest dwellers clad in a reddish-brown coat are our most distant relatives within the great ape family.
The orangutan differs from all of the others because the male can go through two different phases of development.
It is for this reason that there are two types of sexually mature males the smaller appearing externally like the female and the larger developing secondary sexual characteristics such as cheek pads and throat pouches.
which is home to the orangutans. On Sumatra the researchers observed twice as many small males as adults with cheek pads.
which the smaller ones never prevail the advantages of developmental arrest disappear The fact that food supply in the forest has such a strong impact on the mating behaviour of the orangutan came as a surprise to Dunkel.
It goes to show she says that the organisation of these great apes --and perhaps that of our ancestors as well--is more variable than we had assumed hitherto.
but mammals such as horses rhinos and gazelles evolved long strong teeth that are up to the task.
Instead it appears certain South american mammals evolved the teeth in response to the gritty dust
In Argentina mammals apparently developed specialized teeth 20 million years or more before grasslands appeared Strã mberg said.
and western Eurasia where she found the emergence of grasslands coincided with the early ancestors of horses
In the case of Argentine mammals Strã mberg and her co-authors hypothesize that the teeth adapted to handle volcanic ash
--when ancient mammals in that part of the world developed specialized teeth--were overwhelmingly from tropical forests Strã mberg said.
The emergence of grasslands and the evolution of specialized teeth in mammals are regarded as a classic example of co-evolution one that has occurred in various places around the world.
#Extinction looms for forest elephants: 60 percent of Africas forest elephants killed for their ivory over past decadeafrican forest elephants are being poached out of existence.
A study just published in the online journal PLOS ONE shows that across their range in Central africa a staggering 62 percent of all forest elephants have been killed for their ivory over the past decade.
The analysis confirms what conservationists have feared: the rapid trend towards extinction--potentially within the next decade--of the forest elephant says Dr. Samantha Strindberg of the Wildlife Conservation Society (WCS) one of the lead authors of the study.
Saving the species requires a coordinated global effort in the countries where elephants occur--all along the ivory smuggling routes and at the final destination in the Far east.
We don't have much time before elephants are gone says the other lead author Dr. Fiona Maisels also of WCS.
The study which examines the largest ever amount of Central African elephant survey data comes as 178 countries gather in Bangkok to discuss wildlife trade issues including poaching and ivory smuggling.
The study--the largest ever conducted on the African forest elephant--includes the work of more than 60 scientists between 2002 and 2011
and an immense effort by national conservation staff who spent 91600 person-days surveying for elephants in five countries (Cameroon Central african republic the Democratic Republic of congo Gabon
and the Republic of congo) walking over 13000 kilometers (more than 8000 miles) and recording over 11000 samples for the analysis. The paper shows that almost a third of the land where African forest elephants were able to live 10 years ago has become too dangerous
for them. Co-author Dr. John Hart of the Lukuru Foundation says: Historically elephants ranged right across the forests of this vast region of over 2 million square kilometers (over 772000 square miles)
but now cower in just a quarter of that area. Although the forest cover remains it is empty of elephants demonstrating that this is not a habitat degradation issue.
This is almost entirely due to poaching. Recent surveys from Democratic Republic of congo showed a major decline of elephants in the Okapi Faunal Reserve considered the last stronghold for elephants in the region.
Results show clearly that forest elephants were increasingly uncommon in places with high human density high infrastructure density such as roads high hunting intensity
and poor governance as indicated by levels of corruption and absence of law enforcement. Distinct from the African savannah elephant the African forest elephant is slightly smaller than its better known relative
and is considered by many to be a separate species. They play a vital role in maintaining the biodiversity of one of Earth's critical carbon sequestering tropical forests.
A rain forest without elephants is a barren place. They bring it to life they create the trails
they disperse the seeds of many of the rainforest trees--elephants are forest gardeners at a vast scale.
If we do not turn the situation around quickly the future of elephants in Africa is doomed.
This has resulted in escalating elephant massacres in areas previously thought to be safe. We have been carrying out surveys in the forests of Gabon for over a decade
and seen an increasing number of elephant carcasses over the years say co-authors Mr. Rostand Aba'a of the Gabon National parks Service and Mr. Marc Ella Akou of WWF Gabon.
Earlier this month the government of Gabon announced the loss of approximately 11000 forest elephants in Mink b National park between 2004 and 2012;
previously holding Africa's largest forest elephant population. President Ali Bongo Ondimba of Gabon says:
Gabon's elephants are under siege because of an illegal international market that has driven ivory prices in the region up significantly.
If we do not reverse the tide fast the African elephant will be exterminated. Dr. George Wittemyer of Save the Elephants and Colorado State university says:
This study provides unequivocal evidence of the rapid demise of one of the planet's most charismatic and intelligent species. The world must wake up to stem this destruction of species due to conspicuous consumption.
Effective rapid multilevel action is imperative to save elephants. A drastic increase of funding and an immediate focus on the most effective protection strategies are essential to avoid future huge losses to the remaining elephant populations.
Dr. Stephen Blake of the Max Planck Institute says: Forest elephants need two things: they need adequate space in
which to range normally and they need protection. Unprotected roads most often associated with exploitation for timber
or other natural resources push deeper and deeper into the wilderness tolling the death knell for forest elephants.
if forest elephants are to survive. ZSL's West and North africa Programme Manager Mr Chris Ransom says:
if elephants are to survive. The authors of the paper--titled Devastating Decline in Forest Elephants in Central africa--are:
Fiona Maisels Samantha Strindberg Stephen Blake George Wittemyer John Hart Elizabeth A. Williamson Rostand Aba'a Gaspard Abitsi Ruffin D. Ambahe Fidel
) Dian Fossey Gorilla Foundation International the Jane Goodall Institute Lukuru Foundation Zoological Society of London Fauna and Flora International Max Planck Institute San diego
Fossey Gorilla Foundation International Espã ces Phares (European union) Ecosystã mes Forestiers d'Afrique Centrale ECOFAC) Fauna and Flora International Frankfurt Zoological
International Development (USAID CARPE) USFWS Great ape Conservation Fund USFWS African elephant Conservation Fund Wildlife Conservation Society World Wildlife Fund and the Zoological Society
And you could give yourself a gold medal for being a bona fide recycling polar-bear-saving rock star.
The rest was horse impala hartebeest wildebeest waterbok eland gemsbok duiker giraffe kangaroo lamb pork or beef.
Worryingly one sample labelled zebra was actually mountain zebra a'red listed'species threatened with extinction.
#when theres nowhere elseecologists have evidence that some endangered primates and large cats faced with relentless human encroachment will seek sanctuary in the sultry thickets of mangrove
and peat swamp forests. These harsh coastal biomes are characterized by thick vegetation--particularly clusters of salt-loving mangrove trees
when keeping tabs on the distribution of threatened animals such as Sumatran orangutans and Javan leopards according to a recent Princeton university study in the journal Folia Primatologica.
and mangrove swamps as current--and possibly future--wildlife refuges Katarzyna Nowak a former postdoctoral researcher of ecology and evolutionary biology at Princeton compiled a list of 60 primates
and 20 felids (the large-cat family that includes tigers and leopards) known to divide their time between their natural forest habitats and some 47 swamp forests in Africa and Asia.
Because swamp forests often lack food sources fresh water and easy mobility few mammals are exclusive to these areas Nowak reported.
Consequently conservation groups have not intensely monitored the animals'swamp use. But the presence of endangered cats and primates in swamp forests might be overlooked seriously Nowak found.
About 55 percent of Old world monkeys--primates such as baboons and macaques that are native to Africa
and Asia--take to the swamps either regularly seasonally or as needed. In 2008 the Wildlife Conservation Society reported that the inaccessible Lake T l swamp forest in the Republic of the Congo was home to 125000 lowland gorillas--more than were thought to exist in the wild.
Among big cats the Bengal tiger for instance holds its sole ground in Bangladesh in the Sundarbans the world's largest mangrove forest.
Life in the swamps can still be harsh for some animals. Species such as the crab-eating macaque and fishing cat can adapt somewhat readily to a life of swimming
and foraging for crustaceans. Meanwhile Zanzibar's red colobus monkey--driven to coastal mangroves by deforestation--can struggle to find the freshwater it needs as Nowak reported in the American Journal of Primatology in 2008.
Such a trend could result in local extinction of the red colobus nonetheless she said.
Nowak concludes that swamp forests beg further exploration as places where endangered species such as lowland gorillas
and flat-headed cats have preserved their numbers --and where humans could potentially preserve them into the future.
The paper Mangrove and Peat Swamp Forests: Refuge Habitats for Primates and Felids was published in the journal Folia Primatologica.
Story Source: The above story is provided based on materials by Princeton university. Note: Materials may be edited for content and length.
#Democratic Republic of congos best run reserve is hemorrhaging elephantsthe Democratic Republic of congo's (DRC) largest remaining forest elephant population located in the Okapi Faunal Reserve (OFR) has declined by 37 percent in the last five years
with only 1700 elephants now remaining according to wildlife surveys by WCS and DRC officials. WCS scientists warn that
if poaching of forest elephants in DRC continues unabated the species could be extinguished nearly from Africa's second largest country within ten years.
According to the latest survey 5100 or 75 percent of the reserve's elephants have been killed in the last 15 years.
According to WCS the primary reason for the recent decline in forest elephant numbers is ivory poaching.
The survey comes in the wake of another grim report earlier this month from Gabon where 11000 elephants were slaughtered in Minkebe National park over a ten-year period.
WCS continue to sound the alarm that rampant poaching is decimating elephant populations throughout Africa
The global poaching crisis for elephants is at epidemic proportions said WCS Executive vice president for Conservation and Science John Robinson.
and demand or we will lose elephants in the wild in our lifetime. In the early 1990s before the civil war of 1996-2003 DRC was relatively calm.
In a 1995-1997 survey of the OFR--a UNESCO World Heritage Site--WCS found that there were approximately 6800 forest elephants living in an area of almost 14000 km2 (8682 square miles.
After the civil war WCS carried out a second survey in 2005-2007 and found that elephants had suffered heavy losses to poaching with numbers having dropped by 60 percent to approximately 2700 elephants.
For example in Salonga National park a huge area that once held the largest elephant population in DRC WCS found that elephants had been decimated to less than 1000 individuals.
Thus by 2007 OFR had DRC's largest remaining forest elephant population. During the war park guards could not protect much of OFR
but were able to document elephant kills and ivory poaching. Since the end of the civil war five years ago park rangers have reduced the decline from approximately 400 to 170 elephants annually.
Despite this success the park rangers cannot keep up with the dramatic increase in demand for ivory that is being fueled by economic growth in Asia particularly China
Despite these hard realities OFR remains the most important site for the conservation of forest elephants and other large mammals in DRC.
Additional results from recent surveys show that other wildlife in the reserve fared much better including the highly important eastern chimpanzee population (approximately 6000 individuals) okapi and duikers (small forest antelopes) with almost no change in their estimated
and will continue to work in their country to protect elephants and the landscapes where they live.
We urge the international community to support the DRC in the fight against the threat of extinction of the forest elephant.
WCS works to stop the killing by collaborating with partners to prevent criminals from slaughtering elephants in Africa's worst killing fields.
and include sniffer dogs to detect ivory and working with judiciaries and other agencies to increase the number of cases taken to court and rates of successful prosecutions.
The authors examined the effect of GSSE processed from a grape cultivar('Carignan')of Vitis vinifera from northern Tunisia on rats.
Rats were fed a high-fat diet that induced a low-grade reno-lipotoxicity that is kidney damage associated with lipids.
and prevents copper depletion in rats is available Open Access in the journal Applied Physiology Nutrition and Metabolism.
Macroscopic remains of maize (kernels leaves stalks and cobs) were rare. However the team looked deeper and found an abundance of microscopic evidence of maize in various forms in the excavations.
Among 62 coprolites analyzed of all types--34 human 16 domesticated dog and others from various animals--43 (or 69 percent) contained maize starch grains phytoliths
This research which is being conducted by Agricultural research service (ARS) scientists at the agency's Agroecosystems Management Research Unit in Lincoln Neb. supports the USDA priority of ensuring food safety.
--whereas the communicative waggles of bees or the short audible messages of primates are more like the lexical layer.
other primates can make a range of sounds comprising warnings about predators and other messages.
or primates--but like birds we also have a melodic capacity and an ability to recombine parts of our uttered language.
and other primates could all be sources of further research insight. MIT-based research in linguistics has largely been characterized by the search for universal aspects of all human languages.
and integrated the effects of large plant-eating mammals in a 10-year arctic field experiment.
if populations of caribou musk ox and other large herbivores remain intact. The study demonstrates that grazing by these large herbivores maintains plant species diversity
Some areas on which these warming chambers were placed were left open to grazing by caribou and musk ox--two ecologically important large herbivores in the Arctic--while separate 800-square-meter areas that also received warming chambers were fenced off to exclude the animals.
This study confirmed that caribou and musk ox act as a buffer against the degradative effects of warming on plant species diversity Post said.
On the other hand in those areas where caribou and musk ox were able to graze freely shrub responses to warming were muted
Higgins describes studies showing that rats fed resistant starch show decreased numbers and sizes of lesions due to colorectal cancer and an increased number of cells that express the protein IL-10 which acts to regulate the body's inflammatory response Resistant starch may also have implications for the prevention
For example if you let rats get obese get them to lose the weight and then feed half of the rats a diet high in resistant starch--these rats don't gain back the weight as fast as rats fed a regular digestible starch diet.
This effect on obesity may help to reduce breast cancer risk as well as having implications for the treatment of colorectal cancer.
Much of this information currently comes from rodent models and small clinical trials but the evidence is encouraging.
Lead author Kristen Beavers Ph d. and colleagues at Wake Forest Baptist said the findings suggest that prevention of age-related declines in walking speed isn't just about preserving muscle mass it's also about preventing fat gain.
Walking speed declines with age said Beavers and in older adults slower walking speed is a predictor of disability nursing home admission and even death.
Unfortunately said Beavers not much is known about what precedes this decline although change in body composition seemed like a reasonable place to start the research.
Importantly said Beavers older adults who gained the most thigh fat and lost the most thigh muscle were at greatest risk of experiencing a clinically meaningful decline in walking speed.
Beavers said this study is the first of its kind to address the independent association between changes in sophisticated measures of body composition and walking speed.
As the burden of disability becomes increasingly common and expensive identification of modifiable contributors to functional decline in older adults is emerging as a significant priority of public health research Beavers said.
Daniel P. Beavers Ph d. Denise K. Houston Ph d. Barbara J. Nicklas and Stephen Kritchevsky all of Wake Forest Baptist;
In Australia for instance the koala is especially vulnerable to wildfires that consume the tree canopy as the animals are slow-moving
If you're trying to understand how a population grows--say you are trying to keep a population of lions going--the first thing you need to know is how many lionesses you have
and mammal species ranging from black-chinned hummingbirds to black bears. A 2007 study by researchers at the University of Northern Arizona estimated that 150 Clark's nutcrackers cached roughly 5 million pinyon pine nuts in a single season benefiting not only the birds themselves but also the pines
#Most comprehensive tree of life shows placental mammal diversity exploded after age of dinosaursan international team of scientists including University of Florida researchers has generated the most comprehensive tree of life to date on placental mammals
which are those bearing live young including bats rodents whales and humans. Appearing February 7 in the journal Science the study details how researchers used both genetic and physical traits to reconstruct the common ancestor of placental mammals the creature that gave rise to many mammals alive today.
The data show that contrary to a commonly held theory the group diversified after the extinction of dinosaurs 65 million years ago.
The research may help scientists better understand how mammals survived past climate change and how they may be impacted by future environmental conditions.
and fossil primates including lemurs monkeys and humans as well as their closest living relatives flying lemurs and tree shrews.
and fossil mammals before asking questions about'how'and'why'said co-author Jonathan Bloch associate curator of vertebrate paleontology at the Florida Museum of Natural history on the UF campus. This gives us a new perspective of how major change can influence the history
of life like the extinction of the dinosaurs--this was a major event in Earth's history that potentially then results in setting the framework for the entire ordinal diversification of mammals including our own very distant ancestors.
Researchers recorded observational traits for 86 placental mammal species including 40 fossil species. The resulting database contains more than 12000 images that correspond to more than 4500 traits detailing characteristics like the presence or absence
or not shared with other groups of mammals. This study is a great backbone for future work.
and one fossil species from the clade Euarchonta which includes primates tree shrews and flying lemurs. I think this database is amazing
The evolutionary history of placental mammals has been interpreted in very different ways depending on the data analyzed. One leading analysis based on genomic data alone predicted that a number of placental mammal lineages existed in the Late Cretaceous
and survived the Cretaceous-Paleogene extinction. It has been suggested that primates diverged from other mammals well before the extinction of the dinosaurs
but our work using direct evidence from the fossil record tells a different story Bloch said.
The team reconstructed the anatomy of the placental common ancestor by mapping traits most strongly supported by the data to determine it had horned a two uterus a brain with a convoluted cerebral cortex and a placenta in
Knoell's lab previously showed that zinc-deficient mice developed overwhelming inflammation in response to sepsis compared to mice on a normal diet.
Zinc supplementation improved outcomes in the zinc-deficient mice. Until now the beneficial effects of zinc in combating infection have not been understood fully at the molecular level.
In this work Knoell and colleagues sought to zero in on zinc's role in preventing the inflammation that had led to such poor outcomes in the zinc-deficient mice.
When researchers allowed this protein to function unchecked in mice with zinc deficiency the animals developed excessive inflammation in response to sepsis--confirmation that IKKB was zinc's target to turn off the inflammatory pathway.
and the early Paleogene when mammals began to diversify. Lee and colleagues found that the planet's greenhouse-icehouse oscillations are a natural consequence of plate tectonics.
#11,000 elephants slaughtered in national park once home to Africa s largest forest elephant populationthe Wildlife Conservation Society (WCS) announced February 6 that a national park once home to Africa's largest forest elephant
The shocking figures come from Gabon's Minkebe Park where recent surveys of areas within the park revealed that two thirds of its elephants have vanished since 2004.
Gabon contains over half of Africa's forest elephants with a population estimated at over 40000.
) The survey was funded by ANPN the CITES MIKE (Monitoring the Illegal Killing of Elephants) Program and the United states Fish and Wildlife Service.
This sad news from Gabon confirms that without a global commitment great elephant populations will soon become a thing of the past said WCS President and CEO Cristiã¡
We believe that elephants can still be saved --but only if nations greatly increase their efforts to stop poaching
Until recently Gabon's elephant herds were believed to be impacted less by poaching than in other parts of Africa where according to the Born Free Foundation an estimated 31800 individuals were lost to poaching last year.
However Gabon's National park Agency reported an uptick of poaching in recent years including the 2011 slaughter of 27 elephants in a protected area just outside of the capitol.
Park authorities estimated that 50-100 elephants were being killed daily as a result of increases in demand for ivory from the Far east and resulting price hike.
Over the last three years we have deployed 400 additional parks staff 120 soldiers and 30 gendarmes in our fight to stop illegal killing of elephants for the black market ivory trade.
Despite our efforts we continue to lose elephants every day. If we do not turn the situation around quickly the future of the elephant in Africa is doomed.
These new results illustrate starkly just how dramatic the situation has become. Our actions over the coming decade will determine
if we are to save the elephant. Story Source: The above story is provided based on materials by Wildlife Conservation Society.
Microorganisms in the rumen--the largest chamber in the cow's stomach--modify most of the ingested fats and turn them into saturated fats.
In addition albatross are threatened by invasive species such as rats and wild cats which prey on chicks nesting adults and eggs.
Albatross evolved on islands where land mammals were absent so have no defenses against them.
#Low rainfall and extreme temperatures double risk of baby elephant deathsextremes of temperature and rainfall are affecting the survival of elephants working in timber camps in Myanmar
and can double the risk of death in calves aged up to five new research from the University of Sheffield has found.
this could decrease the populations of already endangered Asian elephants. The researchers matched monthly climate records with data on birth and deaths to track how climate variation affects the chances of elephant survival.
It is hoped this research--which was published in the journal Ecology--will make a difference by highlighting the importance of protecting vulnerable calves in captivity from the effects of climate changeexperts at the University of Sheffield accessed unique recordings of the life
and deaths of more than 8000 elephants from Myanmar spanning three generations throughout almost a century.
The elephants in the database are semi-captive animals working in the timber industry by pushing and dragging logs.
Our results show that the optimal conditions for elephant survival correspond to high rainfall and a moderate temperature of 23 C but that further from those optimal conditions elephant survival was lower.
Overall switching from good to bad climatic conditions within an average year significantly increases mortality rates of elephants of all ages.
The most dramatic example comes from baby elephants whose risk of death before the age of five approximately doubles in the hottest weather in comparison to the optimal moderate temperature for elephant survival.
The researchers found that increases in deaths from heat stroke and infectious diseases accounted for the larger number of deaths during the hot months.
Elephants are vulnerable to heat stress because their large size and because they don't sweat like humans
or pant like dogs to cool down. These results could have important implications for Asian elephant populations both in western zoos where they may experience unfamiliar climate added Hannah
and in range countries where climate may be changing faster than elephants can adapt to it.
It also highlights the importance of protecting vulnerable calves from extremes of temperature because more calves will be needed to maintain the dwindling population of endangered Asian elephants.
The project is funded by the Natural Environment Research Council (NERC) and was carried out at the University of Sheffield and Wissenschaftskolleg zu Berlin and the Leibniz Institute for Zoo and Wildlife Research in Germany.
Story Source: The above story is provided based on materials by University of Sheffield. Note: Materials may be edited for content and length.
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