If dinosaurs had been fatter, they might still be around. That's the theory of a team of researchers at New York Medical College that a lack of heat-generating tissue may have led to the demise of dinosaurs.

    Humans, like all mammals, have two kinds of adipose tissue, white fat and brown fat. White fat is used for storing energy-rich fuels, while brown fat generates heat. Hibernating bears have a lot of brown fat, as do human infants, who have much more than adults, relative to their body size. Infants’brown fat protects them from hypothermia.

    Clinicians would like to find ways of making adult white fat behave more like brown fat so that we could burn, rather than store, energy.

    While most mammals have a key gene called UCP1, which is responsible for the heat-generation function of brown fat, birds do not. The researchers found they could induce a specific type of stem cell in chicken embryos to produce differentiated cells that are structured and behave like brown fat. These chicken cells can even activate a UCP1 gene if presented with one from a mouse.

    The ability to produce brown fat evolved in a common ancestor of birds and mammals, but the ability to generate heat was lost in the group that gave rise to birds and lizards after it separated from the mammalian lineage (the researchers found the lizard genome similarly lacks a UCP1 gene). This strongly implies that dinosaurs, which diverged from birds even later than lizards, also lacked brown fat.

The serval cat still was missing Friday afternoon, at least 10 days after escaping the West Michigan Society for the Protection and Care of Animals shelter at 6806 E. Evanston.

The bear, which had been missing for about a week, was recaptured Tuesday evening by SPCA volunteers.

A Michigan Department of Natural Resources official said the serval, a meat-eating predator like all felines, might pose a danger to small domestic animals such as chickens and pet cats.

But SPCA co-owner Brenda Pearson says that's probably not the case with this serval, which has been declawed.

"The serval that is missing is not much more than a small animal itself," she wrote in an e-mail to the Chronicle Friday afternoon. "Although he is leggy, he only weighs about 20 pounds. Their diet would consist of rodents the size of mice."

Brenda Pearson's e-mails, sent in response to a reporter's query, came after repeated telephone requests since Wednesday morning for comment.

Both the serval and the bear are believed to have escaped April 28 or 29. Numerous residents in Fruitport Township reported seeing the bear early this week before it was recovered.

Brenda and Jim Pearson own the Evanston Avenue facility, a 34-acre sanctuary for injured or orphaned wild animals and abused or abandoned exotic animals and other pets.

The DNR is investigating the facility and executed a search warrant Wednesday night to see whether it holds the proper permits for all the animals lodged at the shelter. DNR spokeswoman Mary Dettloff said the agency probably will seek a misdemeanor charge against the owners for failure to report the missing bear, as required by the SPCA's permit.

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When the first duck-billed platypus specimens were sent from Australia to Europe at the end of the 18th century, the bizarre combination of mammal, bird and reptile features led many zoologists to consider them a hoax.

The reason for that first impression has now been revealed: the first analysis of its DNA code has shown that at a genetic level the platypus is indeed a unique amalgam of mammal, reptile and bird.

The platypus genome, sequenced from a female named Glennie, has allowed scientists to examine how evolution shaped not only the strange egg-laying mammal, but also relatives such as human beings. It may even offer insights into human diseases, by revealing genes that are critical to the mammalian immune system.

“This is our ticket back in time, to when all mammals laid eggs while suckling their young on milk,” said Chris Ponting, of the University of Oxford, one of the leaders of the international research team.

“The platyus genome is extremely important, because it is the missing link in our understanding of how we and other mammals first evolved.”

Francis Collins, director of the US National Human Genome Research Institute, said: “At first glance, the platypus appears as if it was the result of an evolutionary accident. But as weird as this animal looks, its genome sequence is priceless for understanding how fundamental mammalian biological processes have evolved.

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When Big Mo died in March at the Pittsburgh Zoo & PPG Aquarium, the yellow-footed tortoise was reputed to be more than 70 years old.

What a piker.

In the world of tortoises, Big Mo was venerable, but hardly a record-holder. The largest of the tortoises, the Galapagos and Aldabra varieties, have been known to live to 150 and possibly longer.

When the Galapagos tortoise Harriet died two years ago in the Australia Zoo, she was not only rumored to be 176, but to be one of the tortoises that were picked up during Charles Darwin's original expedition to the Galapagos Islands.

But even if the oldest tortoises only go back as far as the Spanish-American War rather than the Civil War, their life spans are still amazing, and they raise an intriguing question: What is it about tortoise biology that makes them so long-lived?

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Alaska Native and environmental groups sued Monday to stop exploration by oil companies this summer in Arctic waters frequented by whales, seals and other marine species.

The groups are challenging federal permits that allow Shell Oil Co. and BP PLC to search for oil and gas using powerful acoustic devices that have been shown, at times, to harm a variety of marine animals.

The technology, known as seismic exploration, is used to determine the geologic makeup of the sea bed.

"The federal government is rushing to approve a burst of new seismic activity without completely studying the effects on marine life," said attorney Clayton Jernigan of Earthjustice. The nonprofit law firm's Juneau office filed the lawsuit in U.S. District Court in Anchorage.

The acoustic signals could disrupt tens of thousands of animals as they feed, socialize and travel through the seas of northern Alaska, according to the lawsuit.

This is especially worrisome to Alaska Natives in the region who depend on the marine mammals for food and worry they will desert traditional hunting areas for quieter waters.

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A team of Filipino and American scientists have rediscovered a highly distinctive mammal a greater dwarf cloud rat that was last seen 112 years ago. Furthermore, it has never before been discovered in its natural habitat and was thought by some to be extinct.The greater dwarf cloud rat (Carpomys melanurus) has dense, soft reddish-brown fur, a black mask around large dark eyes, small rounded ears, a broad and blunt snout, and a long tail covered with dark hair. An adult weighs about 185 grams.

"This beautiful little animal was seen by biologists only once previously by a British researcher in 1896 who was given several specimens by local people, so he knew almost nothing about the ecology of the species," said Lawrence Heaney, Curator of Mammals at the Field Museum and Project Leader. "Since then, the species has been a mystery, in part because there is virtually no forest left on Mt. Data, where it was first found."

On 24 April, the research team completed its field work, the first comprehensive survey of the small mammals of Mt. Pulag National Park, according to Samuel Penafiel, the Regional Executive Director for the Philippine Department of Environment and Natural Resources for the Cordillera Administrative Region. Among the results was the capture of the dwarf cloud rat, which is a smaller relative of the giant clouds rats, spectacular animals found only on Luzon Island, but widespread and comparatively well known.

The dwarf cloud rat was captured by Danilo Balete, Project Co-Leader and Research Associate of the Philippine National Museum, in a patch of mature mossy forest (also called cloud forest) high on Mt. Pulag, at about 2,350 meters above sea level. It was in the canopy of a large tree, on a large horizontal branch covered by a thick layer of moss, orchids, and ferns, about 5 meters above ground, Balete said. "We had suspected from its broad, hand-like hind feet that it lived up in big trees, but this is the first evidence to confirm that."

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A recent study has measured the sensitivity to Arctic marine mammals to climate change. The study found that the three species most vulnerable to climate change are the hooded seal, the polar bear, and the narwhal: the common thread between these species being the loss of sea ice.

The narwhal, a strange cetacean with a long tusk unicorn-like at the end of its snout, depends on cod, which live under ice-enclosed seas. The also narwhals spend winters amid the sea ice, which helps them to avoid predators like the orca. Currently, the population of narwhals is unknown, but they are not a common sight in Arctic waters.

The hooded seal also spends the Arctic winter. It uses the sea ice as a birthplace and nursery for their pups. Hooded seals are currently listed by IUCN as 'least concern', but that could change if sea ice continues to diminish at current rates.
The polar bear has become a poster-child for climate change. The loss of sea ice means a loss of prey for the world's largest bear. To survive, the animal would have to adapt different hunting habits. The Bush Administration is currently considering placing the polar bear on the Endangered Species List; the administration, to the frustration of environmentalists, has twice delayed the decision.

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Some of the patients were orphaned. Others were injured after being hit by boats. Ten are in critical condition.

A total of 15 manatees are being cared for at a Lowry Park Zoo hospital devoted to the marine mammals, which is a new record, zoo officials said.

Previously, the highest number admitted at one time to the David A. Straz Jr. Manatee Hospital was 14 in 2003 and 2006.

The newest patients are a 1,625-pound cow and her 69-pound male offspring, zookeepers said.

"As we reach another milestone with our manatee rehabilitation program, we are proud to have the facilities and the expertise to take in these two new manatees and give them a second chance at life," Lex Salisbury, Lowry Park Zoo president and CEO, said.

The zoo operates the only nonprofit manatee hospital in the world dedicated to critical care, according to a news release. About $1 million is spent annually on its manatee rehabilitation program.

It costs about $300 daily to feed an adult manatee and about $30,000 to treat each manatee for one year, officials said.

Since opening the Florida Manatee and Aquatic Center in 1991, the zoo has treated 200 manatees, successfully rehabilitating and releasing half the patients to native habitats. 

The loss of sea ice due to climate change could spell disaster for polar bears and other Arctic marine mammals. Sea ice is the common habitat feature uniting these unique and diverse Arctic inhabitants. Sea ice serves as a platform for resting and reproduction, influences the distribution of food sources, and provides a refuge from predators. The loss of sea ice poses a particularly severe threat to Arctic species, such as the hooded seal, whose natural history is closely tied to, and depends on, sea ice.
The Arctic undergoes dramatic seasonal transformation. Arctic marine mammals appear to be well adapted to the extremes and variability of this environment, having survived past periods of extended warming and cooling.

"However, the rate and scale of current climate change are expected to distinguish current circumstances from those of the past several millennia. These new conditions present unique challenges to the well-being of Arctic marine mammals," says Sue Moore (NOAA/Alaska Fisheries Science Center).

The April Special Issue of Ecological Applications examines such potential effects, puts them in historical context, and describes possible conservation measures to mitigate them. The assessment reflects the latest thinking of experts representing multiple scientific disciplines.

Climate change will pose a variety of threats to marine mammals. For some, such as polar bears, it is likely to reduce the availability of their prey, requiring them to seek alternate food. Authors Bodil Bluhm and Rolf Gradinger (University of Alaska, Fairbanks) note that while some Arctic marine mammal species may be capable of adjusting to changing food availability, others may be handicapped by their very specific food requirements and hunting techniques. Species such as the walrus and polar bear fall under this category, while the beluga whale and bearded seal are among those who are more opportunistic in their eating habits and therefore potentially less vulnerable, at least in this regard.

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Twenty-seven kittens, ranging from blind newborns to fluffy 12-week-olds, snuggled and played in cages at the Floyd County Animal Control shelter Friday, oblivious to their fate.

Shelter Manager Jason Broome said he suspends the four-day euthanasia rule when there’s room to keep the animals but “it’s getting to be kitten season,” when the number of owner-surrendered cats and their young increases beyond capacity.

“We’re not the bad guys here,” said Senior Animal Control Officer John Satterfield, who cites stray dogs as the source of most complaints. “The problem is irresponsible owners.”

The department’s three road officers answer an average 560 to 570 calls a month and impound about 130 dogs, cats, snakes, pigs and other creatures each week.

Some are left behind when their owners move or grow tired of them. Others are chained or penned without access to food and water. And some are out roaming damaging gardens, barking for hours, chasing children or attacking people and pets.

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