Only in the last 5-10000 years have started humans drinking the milk of other animals following advances in our ability to herd animals.
In times of plenty being able to drink the milk of other animals would not have given a particular advantage to those with lactase persistence.
However in situations where food sources became scarce individuals capable of producing lactase as adults would be able to drink the milk of their animals increasing their chances of survival.
#Protect corridors to save tigers, leopardsresearch by Clemson University conservation geneticists makes the case that landscape-level tiger
and leopard conservation that includes protecting the corridors the big cats use for travel between habitat patches is the most effective conservation strategy for their long-term survival.
Sandeep Sharma and Trishna Dutta with colleagues from the Smithsonian Conservation Biology Institute reveal their findings in articles in the Proceedings of the Royal Society B:
Their articles say that forest corridors play an essential role in maintaining the flow of genes between tiger
and leopard populations in central India and are paramount for sustaining the genetic variation required for their long-term persistence.
In the first ever gene-flow analysis of these big cats Sharma and Dutta analyzed the genes of the estimated 273 tigers
and 217 leopards living in four distinct populations in the 17375-mile Satpura-Maikal region of central India then used computer modeling to compare contemporary and historical gene flow among the region's tiger
and leopard populations. The genetic data showed that the region's tiger population divided rapidly twice in history:
First into two clusters about 700 years ago when great swathes of central India's forestland were cleared for agricultural use during the early Mughal era;
then into four clusters around 200 years ago when The british Empire cut vast tracts of timber to build railroads and ships.
This period also corresponded with a huge increase in tiger hunting. Today these big cats live at high densities in the four protected areas.
Some of the areas are connected by relatively contiguous corridors of forest while others are connected by sparse and fragmented corridors.
while the flow of genes between the four tiger and leopard populations has decreased over time clusters linked by contiguous forest corridors have maintained a high rate of gene flow.
Reserves that have lost connectivity between them have seen the greatest decline in gene flow The research suggests that given the fact of limited financial and human capital the big cats would be served better by extending conservation efforts beyond source habitats to a larger landscape scale.
The viability of the forest corridors connecting tiger habitats has a direct affect on a tigers'chance of finding an unrelated mate
and on the ability of tiger populations to maintain genetic diversity Dutta said. As we know genetic diversity allows species to survive disease
Currently central India's tiger corridors have no legal protection and the Indian Ministry of Environment and Forests recently gave permission for coal mining development in a key forest corridor connecting two of the habitats in the study.
and a genetic bottleneck occurs dramatic human intervention is required to save isolated populations of cats from the perils of inbreeding.
Wildlife biologists are forced sometimes to move animals from one population to another. In places where breeding and migratory patterns have been disrupted
Moving animals is inefficient costly and stressful for the animals. There is also no guarantee that the animals will mate Sharma said.
And building manmade corridors is very expensive and logistically challenging. Since we now know that the existing corridors play such a vital role in long-term survival the best way to enable their success is to take a landscape-scale approach to conservation
#Targeting mosquito breeding sites could boost malaria control efforts in Africa and Asiaa malaria control method that targets mosquito larvae and pupae as they mature in standing water could be an important supplementary measure in the fight against the disease according to a new report.
The Cochrane review--led by the London School of Hygiene & Tropical Medicine in collaboration with Durham University and other researchers in the UK and US--is the first systematic review looking at using larval source management (LSM) to control malaria
It found evidence that the method may significantly reduce both the number of cases of malaria by up to 75%and the proportion of people infected with the malaria parasite by up to 90%when used in appropriate settings.
LSM is a method that targets immature mosquitoes found in standing water before the females develop into flying adults that are capable of transmitting malaria.
making temporary changes to mosquito habitats to disrupt breeding for example by clearing drains to make the water flow;
However this success is threatened now by factors such as a growing resistance to insecticides among mosquitoes.
Complementary methods of mosquito control such as LSM may become increasingly necessary in helping tackle the disease
and a sufficient proportion of these habitats can be targeted LSM may reduce the number of cases of malaria and the proportion of people infected with the malaria parasite at any one time.
and rice paddies where mosquitoes breed and building dams flushing streams and removing water containers from around people's homes.
and rural areas of Africa and Asia--wherever it is possible to target a sufficient proportion of mosquito breeding sites.
The tremendous progress made in malaria control in the last decade is threatened now by mosquito resistance to the insecticides available for long-lasting insecticide treated nets and indoor residual spraying.
Thus additional methods are needed to target malaria-transmitting mosquitoes. Our research shows that larval source management could be an effective supplementary intervention in some places.
One study included in the review was from The gambia where mosquitoes were breeding in large swamps and rice paddies;
#Woodland salamanders indicators of forest ecosystem recoverywoodland salamanders are a viable indicator of forest ecosystem recovery according to researchers from the U s. Forest Service's Pacific Southwest Research Station.
PSW Research Wildlife Biologist Dr. Hartwell Welsh and Garth Hodgson examined two species of woodland salamanders across four stages of tree development at Mill Creek--a disturbed
and body condition of two common species of salamander tracked closely with forest stand growth development and structural changes.
Using salamander population numbers and physiological condition on adjacent never harvested old-growth parkland to reference advancements along this developmental pathway they demonstrated relationships between salamander counts
and body condition and aspects of forest advancement including stand age tree size ambient moisture canopy closure
when woodland salamanders are found in high abundance it indicates a healthy forest having undergone ecological advancement and ecosystem recovery.
however amphibians are increasingly becoming accepted as researchers verify their applicability and usefulness. The woodland salamanders evaluated in Mill Creek were deemed credible due to their conservatism trophic role
and high site fidelity which tie them closely to conditions of place. The findings of this case study are important
#Parasitic worm genome uncovers potential drug targetsresearchers have identified five enzymes that are essential to the survival of a parasitic worm that infects livestock worldwide
or the barber pole worm a well-studied parasitic worm that resides in the gut of sheep and other livestock globally.
This genome could provide a comprehensive understanding of how treatments against parasitic worms work and point to further new treatments and vaccines.
The Barber pole worm or H. contortus is part of a family of gastrointestinal worms that are endemic on 100%of farms
H. contortus has become resistant to all major treatments against parasitic worms so its genome is a good model to understand how drug resistance develops in this complex group of closely related parasites
and other worms of this type acquire resistance to a wide range of anthelmintics#the drugs used to treat worm infections#says Dr James Cotton senior author from the Wellcome Trust Sanger Institute.#
because both people and animals are reliant on so few treatments against parasitic worms.##The team sequenced the genome of a strain of H contortus that was susceptible to all major classes of drugs against parasitic worms.
By comparing this sequence with that of worms that have acquired drug resistance the researchers expect to reveal a wealth of information about how
and other types of parasitic worms#says Professor Neil Sargison author from the University of Edinburgh Royal (Dick) School of Veterinary Studies.#
and develop new drugs against parasitic worms to address this issue.##To generate a rich source of potential vaccine
one against Mycobacterium tuberculosis and another against another type of worm. To discover these targets the team determined
or off in the cells and tissues of H. contortus to reveal new insights into the worm s lifecycle.
The result is the most extensive dataset of its kind for any gastrointestinal worm and is expected to provide a valuable resource for future investigations.
#oenot only is this worm closely related to many other parasites of livestock it is also similar to some species of worms in humans.#
#oerevealing new drug targets against H. contortus could provide much-needed new treatment opportunities against parasitic worms in both animals and humans.
The new opportunities for trees and bushes may oust Arctic animals and plants but could also be beneficial to the Greenlanders.
while other species that rely on dispersal by birds or wind first arrived a couple of thousand years later.
and often debilitating osteoarthritis. The researchers found that mice fed a diet rich in the compound had significantly less cartilage damage
We have shown that this works in the three laboratory models we have tried in cartilage cells tissue and mice.
and Aberdeen universities showed there was interaction between the hunter-gatherer and farming communities and a'sharing'of animals and knowledge.
The spread of plants and animals throughout Europe between 6000 and 4000 BC involved a complex interplay between indigenous Mesolithic hunter-gatherers and incoming Neolithic farmers but the scale of the interaction and the extent to
The researchers say previous evidence about the ownership of domestic animals by hunter-gatherers has so far been circumstantial.
Mesolithic hunter-gatherers definitely had dogs but they did not practise agriculture and did not have pigs sheep goats or cows all of
and capturing escaped animals. However the domestic pigs had coloured different and spotted coats that would have seemed strange and exotic to the hunter-gatherers
Furthermore sorghum's special features such as a small diploid genome and phenotypic diversity make it an ideal C4 grass model.
and wedding veil material as insect netting. Anemaet and Middleton were inspired to create an easier method by their field research on baldcypress tree swamps.
Baldcypress swamps are an ecosystem that once spread across the southeastern and eastern United states. They are currently being restored in some areas of the Gulf Coastal plain after years of degradation from agriculture saltwater intrusion and pests like the tent caterpillar.
Each person was shown a picture of a familiar object--such as a chair a pumpkin or a kangaroo--in one eye.
the word for the suppressed object (pumpkin when the object was a pumpkin) the word for a different object (kangaroo
The research in rats published online ahead of print in PLOS ONE found that injections of the compound sodium percarbonate (SPO) can produce enough oxygen to help preserve muscle tissue
Another part of the study involved rats in which the blood flow to a leg was interrupted
or manure on the fields shipped in bat dung from islands in the Pacific or saltpeter from Chilean mines and plowed in glistening granules of synthetic fertilizer made in chemical plants.
New bamboo genera, mountain gorillas, and the origins of Chinas bamboosafrican mountain bamboos are something of a mystery as nearly all bamboos are found in Asia or South america.
Hidden away up mountains in the tropics where they provide food for gorillas just as China's bamboos provide food for the Giant panda there are apparently only 2 species
and they had not been examined in very great detail except by the gorillas see image. It had been thought that they were very closely related to the hundreds of similar bamboos in Asia
but their respective ranges are separated by thousands of miles. As flowering in bamboos is such a rare event spreading by seed takes a very long time
and the bamboos are seen to be as unique as the animals that depend upon them. Story Source:
#Beetles modify emissions of greenhouse gases from cow patscattle contribute to global warming by burping
But now researchers from the University of Helsinki have found that beetles living in cow pats may reduce emissions of the key greenhouse gas--methane.
Now researchers from the University of Helsinki have found that beetles living in the cow pats may reduce emissions of methane.
In fact there are probably as many beetle species living in dung as there are bird species on this planet.
Of the dung beetles living in Northern europe most spend their entire lives within the dung pats.
We believe that these beetles exert much of their impact by simply digging around in the dung.
and the tunneling by beetles seems to aerate the pats. This will have a major impact on how carbon escapes from cow pats into the atmosphere.
If the beetles can keep those methane emissions down well then we should obviously thank them
but the implications also quite worrying says Eleanor Slade a researcher commuting between teams working on dung beetles in both Helsinki and Oxford.
When you combine the current increase in meat consumption around the world with the steep declines in many dung beetle species overall emissions from cattle farming can only increase.
#Red delicious or wolf apple? Brazilian savanna fruits high in antioxidantsnative Brazilian fruits grown in arid climates
The fruits studied here include indigenous species such as lobeira also called'wolf apple'tucum a variety of palm and other fruits
#Ecologists get first bumblebees eye view of the landscapeecologists have produced the most detailed picture yet of how bumblebees use the landscape thanks to DNA technology and remote sensing.
The results--which come from the largest ever study of wild bumblebee nests--could help farmers
and policy makers ensure the countryside is suited better to the needs of these vital but declining pollinators.
Despite their size and often conspicuous colouring bumblebees are difficult to study in the wild
because their nests are almost impossible to find. To work out how far bumblebees forage from their nests a team of ecologists from the Centre for Ecology
and Hydrology (CEH) University of East Anglia University of Bristol and Institute of Zoology instead took advantage of bumblebees'unusual genetics.
According to Dr Matt Heard of CEH: All workers in a bumblebee colony are daughters of a singly-mated queen
which means they are related highly in genetic terms. We decided to exploit this interesting aspect of their biology using a novel combination of genetics field studies
The team sampled DNA non-lethally from live wild bumblebees including 2577 worker and 537 queen bees of five different species. Back in the laboratory they genotyped the samples
The maps allowed the team to estimate the location of each colony as well as how far each bumblebee travelled to find food.
By using the secrets hidden within the DNA of bumblebees we can start to understand how queens
For example reducing the distance that bumblebees have to fly to find food might increase their chances of survival into the next generation
Our findings could help land managers to plan schemes to help conserve bumblebee populations in both agricultural
and other pollinators is less than 0. 1%of the total managed area. Bumblebees are among the most important pollinators of many food crops and wild plants.
The next stage of the research is to use mathematical models to produce a bees'eye view of the landscape.
Dr Claire Carvell the project leader says Ultimately we want to be able to predict which types of landscapes work best for bumblebees
The research is funded by the national Insect Pollinators Initiative. Story Source: The above story is provided based on materials by British Ecological Society (BES.
or disabled by the disease a parasitic-worm infection spread by mosquitoes. Our study quantifies the effect of the most widely implemented vector control measure--insecticide-treated bed nets
but did not stop its transmission by mosquitoes. The success of a strategy utilizing medication requires at least 80 percent of the population to receive treatment annually for at least five years.
Testing showed that parasite levels remained high in mosquitoes around the villages as much as decade later.
they could find no mosquitoes harboring parasites capable of transmitting the disease. Insecticide-treated bed nets already are used widely in areas where lymphatic filariasis
They block female mosquitoes from securing blood a process that is essential for them to lay eggs and produce offspring.
The insecticide reduces the life-span of the insect by half preventing it from living long enough for the parasite to become capable of transmission.
The researchers also discovered that the bed nets caused the insects to alter their biting behavior.
and 2: 00 a m. When the mosquitoes bite earlier in the day they ingest fewer parasites
and evolution of the avian H7n9 influenza virus that emerged in humans in China earlier this year.
Working in three Chinese provinces researchers led by Yi Guan Ph d. of the University of Hong kong collected samples from the throats and digestive tracts of chickens ducks geese pigeons and quail.
The researchers compared the differences between the two sets of sequences to reconstruct how the H7n9 virus evolved through various species of birds
According to their analysis domestic ducks and chickens played distinct roles in the genesis of the H7n9 virus infecting humans today.
Within ducks and later within chickens various strains of avian H7n9 H7n7 and H9n2 influenza exchanged genes with one another in different combinations.
Given these results the authors write continued surveillance of influenza viruses in birds remains essential.
#Forest-interior birds may be benefiting from harvested clearingsefforts to conserve declining populations of forest-interior birds have focused largely on preserving the mature forests where birds breed
In an article published recently in the American Ornithologist Union's publication The Auk research wildlife biologist Scott Stoleson of the U s. Forest Service's Northern Research Station suggests that forest regrowth in clearcuts
may be vital to birds as they prepare for fall migration. The study suggests that declines in forest-interior species may be due in part to the increasing maturity and homogenization of forests.
Openings created by timber harvesting may increase habitat for some forest interior birds according to Stoleson.
On four sites on the Allegheny National Forest and private timber inholdings in northeastern Pennsylvania Stoleson set out to learn where the birds spend time after breeding season and
After the breeding season birds sing less stop defending territory and generally wander. Tracking them is challenging at this point in their life cycle Stoleson said.
Between 2005 and 2008 he used constant-effort mist netting to capture songbirds band them determine
and the extent of parasites the birds carried. In 217 days of netting birds over the course of the 4-year study Stoleson netted
and banded a total of 3845 individuals. Of these 2021 individuals representing 46 species were in the postbreeding stage based on physiological criteria.
Stoleson's research concluded birds'use of young forest in the postbreeding season is correlated with better physiological condition for some forest birds
of which come from the feces of a Southeast Asian animal called a palm civet. Their study appears in ACS'Journal of Agricultural and Food Chemistry.
Eiichiro Fukusaki and colleagues point out that Kopi Luwak (Indonesian for civet coffee) is the world's costliest coffee often fetching $150-$200 per pound.
Palm civets eat coffee berries digest the soft fruit surrounding the bean and excrete the bean. Workers retrieve the coffee beans
#Crocodile confession: Meat-eating predators occasionally eat fruitit turns out that alligators do not live on meat alone.
Neither do Nile crocodiles. A new study led by the Wildlife Conservation Society says that the American alligator
and a dozen other crocodile species enjoy an occasional taste of fruit along with their normal meat-heavy diets of mammals birds and fish.
The study gives new insight into the possible role that crocodilians some of which have large territories may play in forest regeneration through digesting and passing seeds from fruits.
The study appears in the July issue of the Journal of Zoology. Authors include: Steven Platt of the Wildlife Conservation Society;
Ruth M. Elsey of the Louisiana Department of Wildlife and Fisheries; Hong Liu of Florida International University and the Fairchild Tropical Botanic Garden;
The authors looked at 18 species of crocodilian ranging from the American alligator to the fearsome Nile crocodile
Much remains to be learned about how crocodilians process carbohydrates and other plant-based nutrients though studies suggests that fruit eating is likely to yield nutritional rewards for crocodilians.
Although underreported fruit eating appears widespread among crocodilians said the study's lead author Steven Platt of the Wildlife Conservation Society.
Given the biomass of crocodiles in many subtropical and tropical wetlands and their capacity for ingesting large numbers of fruits we consider it likely that crocodilians function as significant seed dispersal agents in many freshwater ecosystems.
Story Source: The above story is provided based on materials by Wildlife Conservation Society. Note: Materials may be edited for content and length.
Journal Reference e
#Honeyguide birds destroy own species eggs to eliminate competitionlike cuckoos honeyguides are parasitic birds that lay their eggs in other birds'nests
and dupe them into raising their young. Now scientists reveal that unlike in cuckoos the resemblance between honeyguide eggs
and those of their bee-eater bird hosts hasn't evolved to trick hosts into accepting the imposter egg as one of their own.
otherwise destroy the eggs because of fierce competition for host nests. The new research is published today 21 august in the journal Biology Letters.
Honeyguides are intriguingly odd birds that are best-known for their unique mutually beneficial relationship with humans.
To obtain it they guide human honey-hunters to bees'nests. In return for showing the humans the bees the honeyguide gains access to the otherwise dangerous and impenetrable nest and its sought-after wax.
But these African birds also have a dark side. They are unusually vicious parasites whose imposter chicks stab the chicks of their host birds (often little bee-eaters) to death
as soon as they hatch in order to eliminate competition for the host parents'care. The newly published research has shown that this fight for monopoly of the nest also extends to other honeyguides in a battle conducted deep underground in the nest burrows that bee-eaters dig into the roofs of Aardvark holes.
The researchers'curiosity was piqued by their earlier finding that like cuckoo eggs honeyguide eggs resemble those of each of their several host species. Instead of mimicking their colour
however they mimic their size (as colour is irrelevant in the dark interior of the deep holes in
which hosts breed). For example honeyguides parasitising little bee-eaters lay smaller eggs in their nests than do honeyguides parasitising larger hosts.
Many classic studies have shown that comparable mimicry in cuckoo eggs has evolved to reduce rejection by choosy hosts that eject mismatched eggs from their nests.
Dr Claire Spottiswoode from the University of Cambridge's Department of Zoology who carried out the research said:
and experimentally parasitised their nests the bee-eaters blithely incubated eggs even much larger than their own.
and about a third of parasitised nests contain eggs laid by two or more honeyguide females resulting in especially strong parasitic competition.
It forms part of a wider research programme investigating coevolution between parasitic birds and their hosts in Zambia led by Dr Claire Spottiswoode who adds My colleagues and
I are very lucky to be helped by a wonderful team of local field assistants who find all the nests we study
and in this case dug many holes into rock-hard soil to reach bee-eater nests and carry out these experiments!
More recently cycads also coexisted with large herbivorous mammals such as the ice age megafauna that only went extinct a few tens of thousands of years ago.
Cycads that are living today have large heavy seeds with a fleshy outer coating that suggests they rely on large bodied fruit-eating animals to disperse their seeds.
and dispersed by today's larger-bodied animals such as emus or elephants. If these plants are adapted for dispersal by a set of animals that has been missing from Earth's fauna for tens of thousands of years then how can they still be around today?
A new study proposes that the clumped dispersal mechanism these ancient plants most likely relied upon still serves them well today.
Naturalists are very comfortable with the idea of animals gaining a biological advantage by choosing to live together in high density'colonies'--such as ant nests or seabird rookeries--in certain parts of the landscape notes Hall.
Australian cycads once coexisted with megafauna that could have dispersed their large heavy seeds--such as giant ground birds bigger then present day emus
and Diprotodon a rhino sized marsupial quadruped explains Hall. The large heavy and poisonous seeds surrounded by a fleshy and nontoxic fruit-like layer seem well adapted to being swallowed occasionally whole en masse by megafauna
Camera traps at two fruiting females and hair traps baited with seeds confirmed the disperser identity.
despite their large seed size the primary dispersers of these cycads today are bodied smaller animals;
these animals do not spread the seeds far and wide nor take them to potentially new colonizable habitats.
Since their potential Australian prehistoric megafaunal dispersers became extinct around 45000 years ago why haven't Australian cycads begun to evolve smaller seeds that would be dispersed more readily by flying birds or possums for example over the interim?
or female and rely completely on host specific insect pollinators--so a lone cycad that dispersed a long way from others of its kind would probably be disadvantaged rather than advantaged in terms of reproduction.
Thus if cycads evolved to be dispersed by large-bodied frugivores these animals would most likely have deposited many cycads seeds in their dung at once
There's no doubt that cycad ancestors were contemporary with herbivorous dinosaurs for many hundreds of millions of years
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