Until its trees started dying, the Colorado ski resort town of Breckenridge stayed out of the business of telling residents how to defend their homes against wildfire.But with trees ravaged by a mountain pine beetle epidemic that has left large rust-tinged swaths of forest vulnerable to a catastrophic fire, town officials decided this year they had to act.
Breckenridge, with a population of 3,500, recently passed an ordinance requiring residents to thin vegetation around their homes -- creating "defensible space" in firefighting lingo -- a move authorities say could help stanch a spreading blaze and aid firefighters in protecting homes.But the new law has infuriated many residents, who call it an encroachment on their rights and demand its repeal."This country has always been based on the idea of private property ownership. It's a sacred thing. The town's ordinance pretty well tramples on that," said Ed Nolan, 65, whose home is surrounded by 37 trees that firefighters say should go.
"If cutting these trees saves my life or my wife's life or a firefighter's life, then it's worth it," countered John Quigley, 59, who has hired a crew to thin some of the 185 trees on his land.California long has required residents in wildfire-prone areas to trim vegetation, and Nevada lawmakers recently approved a similar law for homes in the Tahoe Basin, but other Western states have generally skirted such directives, instead employing public education campaigns to coax residents into doing so. In recent years, many Colorado counties began requiring homeowners in new developments to create defensible space before building permits are issued. But there's nothing authorities can do to compel them to maintain the clearance after they receive their permits, said Kevin Klein, director of the Colorado Division of Fire Safety.Breckenridge's tactic could signal a newly aggressive approach, he said, one that other communities may adopt as Colorado grapples with an infestation that has destroyed thousands of acres of trees and that fire officials fear will contribute to a conflagration."It's a pretty dramatic shift from what we've been doing," said Breckenridge Councilman Jeffrey Bergeron.Surrounded by the White River National Forest, Breckenridge for years has focused more on making hillside homes blend in with their environs by encouraging landscaping around homes, Councilman Dave Rossi said.Then came the beetles. When the town passed a law requiring residents to cut down infected trees, Rossi said few residents objected. But fire officials thought such measures weren't enough. Too many homes were surrounded by brush and trees, said Gary Green, chief of the Red, White and Blue Fire District.Some residents regarded the proposal to require defensible space as necessary to protect the community. Relying on volunteers isn't enough, Quigley said. "If you do it and your three adjoining neighbors don't do it, you haven't accomplished anything," he said.But others have objected to the mandate, citing the expense of removing healthy trees and shrubs and lowered property values."I now have trees that protect the master bedroom from a view of road," Nolan said. "I'm going to pay to lessen the value of my property by taking out these trees."Opponents are circulating a petition seeking to compel the council to repeal the ordinance or put the matter on the ballot. They say they've collected more than the 330 signatures needed to qualify such a measure.The opponents also contend there's scant evidence that the town's approach would be effective against a massive blaze, a criticism the fire chief disputes.They have found a sympathetic ear in Rossi, one of two council members who voted against the ordinance.Though Rossi believes residents should trim vegetation, he questions how effective the strategy can be in one town if neighboring communities don't take the same approach."I'm not sure it gets us where we need to be," said Rossi, noting that the town has not taken other important steps, such as requiring fire-resistant roofing materials.But Bergeron, who was among five council members who supported the ordinance, rejects the argument that the town has overstepped its bounds."I sympathize with people who don't want to cut trees. I'm a tree hugger," he said. "But what I don't buy is the argument that the government can't tell me what to do on my property even if it saves lives and the property of my neighbors.".
Tuesday, July 7, 2009
EPA makes move to regulate greenhouse gases under the Clean Air Act
The Environmental Protection Agency (EPA) issued a finding today that six greenhouse gases cause air pollution that may endanger public health or welfare. The finding also found that emissions from motor vehicles contribute to the concentration of three of those gases, which contributes to climate change.
Air pollution is regulated under the federal Clean Air Act, so this finding is a step toward the EPA implementing regulation of carbon dioxide, which it the primary gas responsible for global warming.
This is a big deal for New Mexico, as the proposed Desert Rock coal-fired power plant in the Four Corners region received an air quality permit from the EPA under the Bush administration, despite protests by the state of New Mexico, environmental organizations and local citizens of the Navajo Nation that the EPA had not considered the impact of carbon dioxide released from the plant into the atmosphere. The the leadership of the greater Navajo Nation itself strongly supports the project.
That air quality permit is currently being appealed by the state of New Mexico.
The six gases are carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons and sulfur hexafluoride.
According to the EPA news release, science “clearly shows” that these gases are at unprecedented concentration levels as the result of human emissions, and that these levels are “very likely” the cause of increased climate temperatures.
The finding states that “In both magnitude and probability, climate change is an enormous problem. The greenhouse gases that are responsible for it endanger public health and welfare within the meaning of the Clean Air Act.”
The EPA statement also said science shows a link between climate change and negative effects on human health. These impacts included higher concentrations of ground-level ozone; increased drought; more heavy downpours and flooding; more frequent and intense heat waves and wildfires; greater sea level rise; more intense storms; and harm to water resources, agriculture, wildlife and ecosystems.
Additionally, the statement said, new EPA Administrator Lisa Jackson took into account the disproportionate impact of these impacts on the health of certain groups of people, “…such as the poor, the very young, the elderly, those already in poor health, the disabled, those living alone and/or indigenous populations dependent on one or a few resources.”
The EPA also stated that global warming is a national security issue as resources like water become more scare forcing mass migrations into more stabilized regions.
This announcement results from a review by the Obama administration of the findings from a prior EPA scientific review ordered by the U.S. Supreme Court in 2007, looking at whether or not greenhouse gases harm the environment. EPA scientists said they did, but the Bush administration suppressed those results, and never acted to regulate the greenhouse gases.
Obama ordered the review shortly after taking office, which was widely expected.
The finding will now be placed in the federal register, and the public has 60 days from that point to provide comments to the EPA. A final rule will be made after that.
Air pollution is regulated under the federal Clean Air Act, so this finding is a step toward the EPA implementing regulation of carbon dioxide, which it the primary gas responsible for global warming.
This is a big deal for New Mexico, as the proposed Desert Rock coal-fired power plant in the Four Corners region received an air quality permit from the EPA under the Bush administration, despite protests by the state of New Mexico, environmental organizations and local citizens of the Navajo Nation that the EPA had not considered the impact of carbon dioxide released from the plant into the atmosphere. The the leadership of the greater Navajo Nation itself strongly supports the project.
That air quality permit is currently being appealed by the state of New Mexico.
The six gases are carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons and sulfur hexafluoride.
According to the EPA news release, science “clearly shows” that these gases are at unprecedented concentration levels as the result of human emissions, and that these levels are “very likely” the cause of increased climate temperatures.
The finding states that “In both magnitude and probability, climate change is an enormous problem. The greenhouse gases that are responsible for it endanger public health and welfare within the meaning of the Clean Air Act.”
The EPA statement also said science shows a link between climate change and negative effects on human health. These impacts included higher concentrations of ground-level ozone; increased drought; more heavy downpours and flooding; more frequent and intense heat waves and wildfires; greater sea level rise; more intense storms; and harm to water resources, agriculture, wildlife and ecosystems.
Additionally, the statement said, new EPA Administrator Lisa Jackson took into account the disproportionate impact of these impacts on the health of certain groups of people, “…such as the poor, the very young, the elderly, those already in poor health, the disabled, those living alone and/or indigenous populations dependent on one or a few resources.”
The EPA also stated that global warming is a national security issue as resources like water become more scare forcing mass migrations into more stabilized regions.
This announcement results from a review by the Obama administration of the findings from a prior EPA scientific review ordered by the U.S. Supreme Court in 2007, looking at whether or not greenhouse gases harm the environment. EPA scientists said they did, but the Bush administration suppressed those results, and never acted to regulate the greenhouse gases.
Obama ordered the review shortly after taking office, which was widely expected.
The finding will now be placed in the federal register, and the public has 60 days from that point to provide comments to the EPA. A final rule will be made after that.
Greenpeace: New Mexico belches more greenhouse gases than 137 countries
According to a report by Greenpeace, New Mexico emitted more global warming pollution from fossil fuel consumption since 1960 than the emissions of 137 of the 184 countries with comprehensive data available.The study looked at each state in the United States compared to the rest of the country. New Mexico had the 11th most per capita carbon emissions from 1960-2005. Wyoming had the most per capita.
In overall emissions, however, New Mexico ranked 19th 33rd among all U.S. states, while Vermont had the least carbon emissions in both counts.
The United States as a whole had 26 percent of the world’s carbon dioxide emissions according to the Greenepeace report. The United States ranked third in per capita carbon dioxide emissions behind just Luxembourg and Estonia.
“Here in New Mexico we are already seeing the effects of climate change on our community,” Greenpeace field organizer Joe Smyth said.
In 2007, New Mexico joined the Western Climate Action Initiative (WCI) along with Arizona, California, Oregon and Washington. The WCI sets a regional global warming emissions reduction goal.
Also, in 2005, New Mexico “established a statewide goal to reduce global warming emissions to 2000 levels by 2012, 10 percent below 2000 levels by 2020, and 75 percent below 2000 levels by 2050.”
“If we want to reduce global warming’s impacts and kick-start a clean energy future we must think not as New Mexicans but as citizens of the world,” Smyth said. “If we let our government get it wrong on global warming, instead of being the planet’s best hope, we will remain its biggest obstacle to progress.”
In overall emissions, however, New Mexico ranked 19th 33rd among all U.S. states, while Vermont had the least carbon emissions in both counts.
The United States as a whole had 26 percent of the world’s carbon dioxide emissions according to the Greenepeace report. The United States ranked third in per capita carbon dioxide emissions behind just Luxembourg and Estonia.
“Here in New Mexico we are already seeing the effects of climate change on our community,” Greenpeace field organizer Joe Smyth said.
In 2007, New Mexico joined the Western Climate Action Initiative (WCI) along with Arizona, California, Oregon and Washington. The WCI sets a regional global warming emissions reduction goal.
Also, in 2005, New Mexico “established a statewide goal to reduce global warming emissions to 2000 levels by 2012, 10 percent below 2000 levels by 2020, and 75 percent below 2000 levels by 2050.”
“If we want to reduce global warming’s impacts and kick-start a clean energy future we must think not as New Mexicans but as citizens of the world,” Smyth said. “If we let our government get it wrong on global warming, instead of being the planet’s best hope, we will remain its biggest obstacle to progress.”
Climate change already changing New Mexico
According to an article in today’s edition of the Albuquerque Journal, a report says that “the effects of human-caused climate change” are already being felt in New Mexico. The effects come in the form of “rising temperatures and dwindling snowpacks.”There looks to be plenty of reason to be concerned. Albuquerque Journal science writer John Fleck tells of some of the effects that man-made climate change will have on New Mexico:
The website for the “Global Climate Change Impacts in the United States” report says, “Recent warming in the Southwest has been among the most rapid in the nation.”
The effects will be felt not only in areas like the agriculture of our region, but also in the “unique tourism and recreation opportunities.”
“Rising temperatures will adversely affect winter activities such as downhill and cross-country skiing, snowshoeing, and snowmobiling,” the Southwest area of the website on the report states.
The website for the “Global Climate Change Impacts in the United States” report says, “Recent warming in the Southwest has been among the most rapid in the nation.”
The effects will be felt not only in areas like the agriculture of our region, but also in the “unique tourism and recreation opportunities.”
“Rising temperatures will adversely affect winter activities such as downhill and cross-country skiing, snowshoeing, and snowmobiling,” the Southwest area of the website on the report states.
Feds allow New Mexico and 13 other states to reduce vehicle greenhouse gas emissions
The U.S. Environmental Protection Agency granted a waiver on Tuesday that allows California and 13 other states, including New Mexico, to create regulations to reduce greenhouse gas emissions in new automobiles, according the governor’s office late Tuesday afternoon.
Gov. Bill Richardson immediately lauded the development.
“This decision gives us the best of both worlds – it validates the leadership of states like New Mexico that have adopted clean vehicle emission standards while demonstrating strong federal leadership to address transportation-related climate pollution in the future,” the governor said in a news release issued by his office.
The federal government’s reversal is a 180-degree turn away from a Bush administration decision to not let states adopt stiffer vehicle emissions standards than the federal government.
New Mexico has been involved in the fight to regulate vehicle emissions for the past year and a half.
The Land of Enchantment in late 2007 adopted the so-called California clean car emissions standards, meaning that it would impose stricter emission standards than the federal government’s on vehicles sold in New Mexico. A month later, however, in December 2007, the then-EPA administrator denied California the waiver to institute the tougher emission standards. No waiver for California getting meant the other states, including New Mexico, couldn’t adopt the tougher standards either.
New Mexico and other states then sued EPA over the denial.
But President Obama asked EPA to reconsider this decision earlier this year.
Transportation is the fastest growing source of greenhouse gas emissions in New Mexico, the state has said in the past. The tougher vehicle emission standards would apply to model year 2011 vehicles and beyond.
“By adopting and defending these standards, states like New Mexico have effected federal action on climate change,” New Mexico’s Environment Department Secretary Ron Curry said in the news release issued by the governor’s office. “The greenhouse gas vehicle standard started in the states and is now becoming a national program. I think we will see a similar trend with the passage of an economy-wide greenhouse gas reduction bill in Congress.”
Gov. Bill Richardson immediately lauded the development.
“This decision gives us the best of both worlds – it validates the leadership of states like New Mexico that have adopted clean vehicle emission standards while demonstrating strong federal leadership to address transportation-related climate pollution in the future,” the governor said in a news release issued by his office.
The federal government’s reversal is a 180-degree turn away from a Bush administration decision to not let states adopt stiffer vehicle emissions standards than the federal government.
New Mexico has been involved in the fight to regulate vehicle emissions for the past year and a half.
The Land of Enchantment in late 2007 adopted the so-called California clean car emissions standards, meaning that it would impose stricter emission standards than the federal government’s on vehicles sold in New Mexico. A month later, however, in December 2007, the then-EPA administrator denied California the waiver to institute the tougher emission standards. No waiver for California getting meant the other states, including New Mexico, couldn’t adopt the tougher standards either.
New Mexico and other states then sued EPA over the denial.
But President Obama asked EPA to reconsider this decision earlier this year.
Transportation is the fastest growing source of greenhouse gas emissions in New Mexico, the state has said in the past. The tougher vehicle emission standards would apply to model year 2011 vehicles and beyond.
“By adopting and defending these standards, states like New Mexico have effected federal action on climate change,” New Mexico’s Environment Department Secretary Ron Curry said in the news release issued by the governor’s office. “The greenhouse gas vehicle standard started in the states and is now becoming a national program. I think we will see a similar trend with the passage of an economy-wide greenhouse gas reduction bill in Congress.”
Honeybee mobs overpower hornets
Honeybee hordes use two weapons - heat and carbon dioxide - to kill their natural enemies, giant hornets.
Japanese honeybees form "bee balls" - mobbing and smothering the predators.
This has previously been referred to as "heat-balling", but a study has now shown that carbon dioxide also plays a role in its lethal effectiveness.
In the journal Naturwissenschaften, the scientists describe how hornets are killed within 10 minutes when they are trapped inside a ball of bees.
Japanese giant hornets, which can be up to 5cm long, are voracious predators that can devastate bees' nests and consume their larvae.
But, if the bees spot their attacker in time, they mount a powerful defence in the form of a bee ball. This study found that the heat inside the bee ball alone was not enough to reliably kill the hornets
"They can survive for 10 minutes at a temperature up to 47C, and the temperature inside the bee balls does not rise higher than 46C," said Fumio Sakamoto, a researcher from Kyoto Gakuen University in Japan, and one of the authors of the study.
His team recreated experimental bee balls and took direct measurements from inside them.
They anaesthetised giant hornets and fixed them to the tip either of a thermometer probe, or the inlet of a gas detector.
Once the hornets recovered from their anaesthesia, the probes were touched to the bees' nest.
"The bee ball formed (around the hornet) immediately," said Dr Sakamoto.
After 10 minutes the bees were packed solidly enough around the probe to be removed from the nest in a distinct ball.
As the temperature inside the ball increased to more than 45C, the carbon dioxide level also rose sharply.
In a parallel experiment, the scientists found that in an atmosphere relatively high in carbon dioxide, the temperature at which hornets could survive for 10 minutes was lowered.
"So we concluded that carbon dioxide produced inside the bee ball by the honeybees is a major factor, together with temperature, involved in the bees' defence."
Dr Sakamoto is not sure, at this point, whether the bees were effectively "gassing" the hornets, or simply depriving them of oxygen.
"Either way, the carbon dioxide increase and/or the oxygen decrease lowered the temperature that was lethal to the hornets, " he told BBC News.
"We are going to do the additional experiments about this point using mixed air of various oxygen and carbon dioxide (concentrations)."
The mob of bees also appeared to operate in "two phases".
"The hornet may be killed during the first 0-5 minute period, in which the highest level of heat production and carbon dioxide emissions take place," said Dr Sakamoto.
This might suggest that the bees are aware of what physiological state the hornet is in.
Dr Sakamoto said: "The latter 5-10 min period may be free running to ensure their victim's death."
Japanese honeybees form "bee balls" - mobbing and smothering the predators.
This has previously been referred to as "heat-balling", but a study has now shown that carbon dioxide also plays a role in its lethal effectiveness.
In the journal Naturwissenschaften, the scientists describe how hornets are killed within 10 minutes when they are trapped inside a ball of bees.
Japanese giant hornets, which can be up to 5cm long, are voracious predators that can devastate bees' nests and consume their larvae.
But, if the bees spot their attacker in time, they mount a powerful defence in the form of a bee ball. This study found that the heat inside the bee ball alone was not enough to reliably kill the hornets
"They can survive for 10 minutes at a temperature up to 47C, and the temperature inside the bee balls does not rise higher than 46C," said Fumio Sakamoto, a researcher from Kyoto Gakuen University in Japan, and one of the authors of the study.
His team recreated experimental bee balls and took direct measurements from inside them.
They anaesthetised giant hornets and fixed them to the tip either of a thermometer probe, or the inlet of a gas detector.
Once the hornets recovered from their anaesthesia, the probes were touched to the bees' nest.
"The bee ball formed (around the hornet) immediately," said Dr Sakamoto.
After 10 minutes the bees were packed solidly enough around the probe to be removed from the nest in a distinct ball.
As the temperature inside the ball increased to more than 45C, the carbon dioxide level also rose sharply.
In a parallel experiment, the scientists found that in an atmosphere relatively high in carbon dioxide, the temperature at which hornets could survive for 10 minutes was lowered.
"So we concluded that carbon dioxide produced inside the bee ball by the honeybees is a major factor, together with temperature, involved in the bees' defence."
Dr Sakamoto is not sure, at this point, whether the bees were effectively "gassing" the hornets, or simply depriving them of oxygen.
"Either way, the carbon dioxide increase and/or the oxygen decrease lowered the temperature that was lethal to the hornets, " he told BBC News.
"We are going to do the additional experiments about this point using mixed air of various oxygen and carbon dioxide (concentrations)."
The mob of bees also appeared to operate in "two phases".
"The hornet may be killed during the first 0-5 minute period, in which the highest level of heat production and carbon dioxide emissions take place," said Dr Sakamoto.
This might suggest that the bees are aware of what physiological state the hornet is in.
Dr Sakamoto said: "The latter 5-10 min period may be free running to ensure their victim's death."
Aquatic deer and ancient whales
If you startled a deer, you might not expect it to jump into the nearest pond and submerge itself for minutes.
But that is exactly what two species of mouse-deer in Asia do when confronted by predators, scientists have found.
One other African mouse-deer species is known to do the same thing, but the new discovery suggests all ruminants may once have had an affinity with water.
It also lends support to the idea that whales evolved from water-loving creatures that looked like small deer.
There are around 10 species of mouse-deer, which are also called 'chevrotains'.
All belong to the ancient ruminant family Tragulidae, which split some 50 million years ago from other ruminants, the group that went on to evolve into cattle, goats, sheep, deer and antelope.
Deer are supposed to walk on land and graze not swim underwater
Zoologist Erik Meijaard
Each are small, deer-like creatures that unusually don't have antlers or horns. Instead they have large upper canine teeth, which in the males project down either side of the lower jaw.
The largest species, which stands no more than 80cm tall, lives in Africa and is thought to be the most primitive of all mouse-deer. Known as the water-chevrotain, this animal likes to live in swampy habitats. When alarmed, it dashes for the nearest river where it submerges and swims underwater to safety.
All of the other species of mouse-deer, which live in southeast Asia and India and Sri Lanka were thought to be dry-land animals.
Diving deer
That was until researchers witnessed some remarkable behaviour during two separate incidents.
The first occurred in June 2008 during a biodiversity survey in northern Central Kalimantan Province in Borneo, Indonesia.
During the survey, observers saw a mouse-deer swimming in a forest stream. When the animal noticed the observers it submerged. Over the next hour, they saw it come to the surface four or five times, and maybe more unseen. But it often remained submerged for more than five minutes at a time.
Eventually the observers caught the animal, which they identified as a pregnant female, then released it unharmed.
Among the survey team was the wife of Erik Meijaard, a senior ecologist working with the Nature Conservancy in Balikpapan, Indonesia.
Meijaard knew of anecdotal reports by local people who described deer hiding in creeks and rivers when chased by their dogs. When he saw photos of the deer he identified it as a greater mouse-deer
The same year, Meijaard also heard reports of a mouse-deer in Sri Lanka that had also been seen swimming underwater.
Three observers saw a mountain mouse-deer (Moschiola spp) run into a pond and start to swim, hotly pursued by a brown mongoose. The mouse-deer submerged itself, and eventually the mongoose retreated. The deer left the water only to be chased straight back into it by the mongoose.
"It came running again and dived into the water and swam underwater. I photographed this clearly and it became clear to me at this stage that swimming was an established part of its escape repertoire," says Gehan de Silva Wijeyeratne, who saw the incident.
"Seeing it swim underwater was a shock. Many mammals can swim in water. But other than those which are adapted for an aquatic existence, swimming is clumsy. The mouse-deer seemed comfortable, it seemed adapted," he says.
Origins of whales
Meijaard, Wijeyeratne and Umilaela, who saw the submerged Bornean mouse-deer, describe both incidents in the journal Mammalian Biology.
"This is the first time that this behaviour has been described for Asian mouse-deer species," says Meijaard. "I was very excited when I heard the mouse-deer stories because it resolved one of those mysteries that local people had told me about but that had remained hidden to science."
"The behaviour is interesting because it is unexpected. Deer are supposed to walk on land and graze not swim underwater. But more interestingly for the zoologist are the evolutionary implications," he says.
The behaviour bolsters one leading theory regarding the origin of whales.
In 2007, scientists led by Hans Thewissen of the Northeastern Ohio Universities College of Medicine in Ohio published details of a remarkable fossil called Indohyus.
This fossil was of a ruminant animal that looked like a small deer, but also had morphological features that showed it could be an ancestor of early whales.
Although speculative, that suggests that all early ruminants may also have led a partially aquatic lifestyle.
The discovery that two Asian species of mouse-deer are comfortable underwater shows that at least three species of modern tragulid share an aquatic escape behaviour.
Because these species diverged at least 35 million years ago, their ancestor also likely behaved in the same way, again bolstering the the idea that a deer-like ruminant may have evolved to produce the modern cetacean group of whales and dolphins.
Hippos, the closest modern relative of whales, also dive for water when threatened, a behaviour that may have been lost over time by other modern species such as sheep and antelope.
But that is exactly what two species of mouse-deer in Asia do when confronted by predators, scientists have found.
One other African mouse-deer species is known to do the same thing, but the new discovery suggests all ruminants may once have had an affinity with water.
It also lends support to the idea that whales evolved from water-loving creatures that looked like small deer.
There are around 10 species of mouse-deer, which are also called 'chevrotains'.
All belong to the ancient ruminant family Tragulidae, which split some 50 million years ago from other ruminants, the group that went on to evolve into cattle, goats, sheep, deer and antelope.
Deer are supposed to walk on land and graze not swim underwater
Zoologist Erik Meijaard
Each are small, deer-like creatures that unusually don't have antlers or horns. Instead they have large upper canine teeth, which in the males project down either side of the lower jaw.
The largest species, which stands no more than 80cm tall, lives in Africa and is thought to be the most primitive of all mouse-deer. Known as the water-chevrotain, this animal likes to live in swampy habitats. When alarmed, it dashes for the nearest river where it submerges and swims underwater to safety.
All of the other species of mouse-deer, which live in southeast Asia and India and Sri Lanka were thought to be dry-land animals.
Diving deer
That was until researchers witnessed some remarkable behaviour during two separate incidents.
The first occurred in June 2008 during a biodiversity survey in northern Central Kalimantan Province in Borneo, Indonesia.
During the survey, observers saw a mouse-deer swimming in a forest stream. When the animal noticed the observers it submerged. Over the next hour, they saw it come to the surface four or five times, and maybe more unseen. But it often remained submerged for more than five minutes at a time.
Eventually the observers caught the animal, which they identified as a pregnant female, then released it unharmed.
Among the survey team was the wife of Erik Meijaard, a senior ecologist working with the Nature Conservancy in Balikpapan, Indonesia.
Meijaard knew of anecdotal reports by local people who described deer hiding in creeks and rivers when chased by their dogs. When he saw photos of the deer he identified it as a greater mouse-deer
The same year, Meijaard also heard reports of a mouse-deer in Sri Lanka that had also been seen swimming underwater.
Three observers saw a mountain mouse-deer (Moschiola spp) run into a pond and start to swim, hotly pursued by a brown mongoose. The mouse-deer submerged itself, and eventually the mongoose retreated. The deer left the water only to be chased straight back into it by the mongoose.
"It came running again and dived into the water and swam underwater. I photographed this clearly and it became clear to me at this stage that swimming was an established part of its escape repertoire," says Gehan de Silva Wijeyeratne, who saw the incident.
"Seeing it swim underwater was a shock. Many mammals can swim in water. But other than those which are adapted for an aquatic existence, swimming is clumsy. The mouse-deer seemed comfortable, it seemed adapted," he says.
Origins of whales
Meijaard, Wijeyeratne and Umilaela, who saw the submerged Bornean mouse-deer, describe both incidents in the journal Mammalian Biology.
"This is the first time that this behaviour has been described for Asian mouse-deer species," says Meijaard. "I was very excited when I heard the mouse-deer stories because it resolved one of those mysteries that local people had told me about but that had remained hidden to science."
"The behaviour is interesting because it is unexpected. Deer are supposed to walk on land and graze not swim underwater. But more interestingly for the zoologist are the evolutionary implications," he says.
The behaviour bolsters one leading theory regarding the origin of whales.
In 2007, scientists led by Hans Thewissen of the Northeastern Ohio Universities College of Medicine in Ohio published details of a remarkable fossil called Indohyus.
This fossil was of a ruminant animal that looked like a small deer, but also had morphological features that showed it could be an ancestor of early whales.
Although speculative, that suggests that all early ruminants may also have led a partially aquatic lifestyle.
The discovery that two Asian species of mouse-deer are comfortable underwater shows that at least three species of modern tragulid share an aquatic escape behaviour.
Because these species diverged at least 35 million years ago, their ancestor also likely behaved in the same way, again bolstering the the idea that a deer-like ruminant may have evolved to produce the modern cetacean group of whales and dolphins.
Hippos, the closest modern relative of whales, also dive for water when threatened, a behaviour that may have been lost over time by other modern species such as sheep and antelope.
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