Archive for December, 2013

Cooking With Gas

Recently I watched a TED talk by Suzana Herculano-Houzel (http://www.suzanaherculanohouzel.com/lab) entitled, “What is so special about the human brain?” (http://www.ted.com/talks/suzana_herculano_houzel_what_is_so_special_about_the_human_brain.html). In this presentation she makes the intriguing assertion that our brain is as large as it is, at least in part, because we cook our food.

Size, as in brain size, is not as important as neuron number when it comes to intelligence. Although the elephant brain is three times as large as the human brain it contains 23 billion neurons, compared with 86 billion in the human brain (http://en.wikipedia.org/wiki/List_of_animals_by_number_of_neurons).

Unfortunately the human brain is incredibly expensive to run, 25% of the energy consumed daily goes to fuel the brain. It costs around 6 kCal to run one billion neurons per day. Despite great apes being physically larger than us, their brains are smaller. Herculano-Houzel proposes that this is because they cannot consume enough calories on a daily basis to run a bigger brain. They do have a fairly low energy diet consisting predominantly of high fibre plant material with a few fruits and, in the chimpanzee’s case, some meat. This may be why the chimpanzee can afford to run 5.5 to 6.2 billion cerebral cortical neurons compared with the gorilla’s 4.3 billion.

However, humans maintain between 19 and 23 billion cerebral cortical neurons. Herculano-Houzel believes we can feed this number because of cooking, which effectively predigests our food releasing more energy and allowing us to more completely absorb our food. She depicts a graph, which correlates the increase in brain size of our ancestors with the invention of cooking.

Paradoxically we are now moving away from cooking and processing back to a more unprocessed diet because we appear to have overdone it, consuming too many calories and becoming extremely obese in the process. If we could only divert all those extra calories to our brains instead of our bodies imagine how incredibly intelligent we could become.

Dr. F. Bunny

 

, , , , , , , , ,

Leave a comment

Tourists Are Giving Endangered Iguanas Diarrhea And High Cholesterol

From Scientific American at http://blogs.scientificamerican.com/extinction-countdown/2013/12/10/tourists-iguanas-diarrhea/.

Hop on over to the photo-sharing site Flickr and you’ll find dozens of photos and videos of people eagerly feeding grapes to hungry iguanas on the beaches of the Bahamas. It looks like great fun and the iguanas obviously go crazy for the fruit, which is usually fed to the lizards on the ends of long sticks. There’s just one problem with this activity: the food is making the iguanas sick. Health conditions arising from the grapes and other foods that iguanas do not normally eat in the wild include diarrhea, high blood sugar and cholesterol as well as lowered levels of potassium and a high level of parasitic infections. All of these problems “could have deleterious effects on long-term fitness and population stability,” according to Charles Knapp, director of conservation and research at Chicago’s John G. Shedd Aquarium and the lead author of a new study of the iguanas published last week in Conservation Physiology.

iguana grapes Bahamian rock iguanas (Cyclura cychlura) live on the islands of Andros and Exuma and several small nearby cays in the island chain. Although not technically endangered, they are considered vulnerable to extinction, with a total wild population of fewer than 5,000 individuals. That count covers the entire species, which also includes three subspecies, two of which are endangered and one of which is critically endangered.

As Knapp and his fellow researchers wrote in the paper, the feeding of wildlife is “an increasingly popular yet under-studied tourism-related activity” that is often sanctioned and encouraged for both marine and terrestrial animals. Sometimes that is beneficial, providing the animals with access to low-stress nutrition and humans with a positive conservation experience. Other times, however, feeding wildlife can cause problems, especially if it includes items from outside of their native diets. Consequences can include nutritional imbalances, obesity or behavior changes that have harmful long-term effects.

Knapp and his team wanted to find out if the hundreds of weekly tourists visiting iguana habitats were having a positive or negative effect on the animals’ health. They traveled to the islands in 2010 and 2012 and examined iguanas that interact with tourists as well as those in more isolated locations. They found that both groups of iguanas appeared the same externally but the tourist-fed iguanas—especially the more aggressive males—showed signs of nutritional imbalance. Many had diarrhea, all of them carried parasites and their blood showed abnormal levels of calcium, glucose, potassium and uric acid. The tourist-fed males also had aberrant amounts of cholesterol, copper, magnesium and other nutrients. The paper links the high-sugar, low-potassium levels to the grapes, Ground beef and other animal proteins could be causing the high cholesterol and uric acid levels found in the iguanas. (The iguanas are normally herbivorous.)

Tourists aren’t the primary threat to Bahamian rock iguanas, however. The species faces habitat loss due to construction, dangerous feral animals such as goats, collection for pet trade and illegal hunting. (They’re the only iguana species still caught for food.) Those threats aren’t going away anytime soon.

In a press release Knapp said that it’s unrealistic to expect tourists to stop feeding the iguanas. “Instead,” he suggested, “wildlife managers could approach manufacturers of pelleted iguana foods and request specially formulated food to mitigate the impact of unhealthy food. Tour operators could offer or sell such pellets to their clients, which would provide a more nutritionally balanced diet and reduce non-selective ingestion of sand on wet fruit.” Done right, the authors suggest, tourism could actually benefit the iguanas and give them the nutrition and safety they need in order to boost their populations. That’s a worthy goal we’re sure the iguanas can get behind, even if it means fewer grapes.

Photo: Iguana reaching for grapes by Chris Dixon via Flickr. Used under Creative Commons license

, , , , , , , , ,

1 Comment

Vaccination of badgers is launched

From the Western Gazette, North Dorset at http://www.westerngazette.co.uk/Vaccination-badgers-launched/story-20314824-detail/story.html#axzz2nO4fAjhg.

CONSERVATIONISTS in Dorset began their own battle against badgers with TB this week, but have begun to vaccinate them instead of culling them.

The Dorset Wildlife Trust said it wants to demonstrate there is a “safe, humane alternative” to badger culling, and has embarked on a five-year programme to vaccinate all the badgers living on some of its nature reserves in the county.

With the prospect of the badger cull moving from west Gloucestershire and west Somerset to Dorset and Wiltshire next year, the Dorset Wildlife Trust said it wanted to show there were “more effective and reliable” ways of controlling bovine TB.

It launched a successful appeal to fund the project, trained volunteers and has now started the five-year programme which has already seen badgers trapped and vaccinated at ‘selected’ locations throughout the county.

“Dorset Wildlife Trust wants to see the eradication of the devastating disease bovine Tuberculosis (bTB) and understands the serious implications for farmers who lose stock as a result, but believes there are more effective and reliable ways of controlling the disease, such as better biosecurity, badger vaccination and, in the long term, cattle vaccination,” said chief executive Dr Simon Cripps.

“Badger vaccination has the potential to reduce bTB without the negative impacts of increasing the transference of bTB among infected and healthy badgers and cattle that culling would bring. We were extremely disappointed to see the Government drive forward with the badger cull in Somerset and Gloucestershire in August this year. The recent news that the pilot culls in Gloucestershire and Somerset have finished with low numbers of badgers being shot, strengthens the need for the Government to support alternative methods to culling.

“Our understanding from Defra is that if badger culling continues despite these failures, shooting in Dorset is highly likely to start in 2014.  Thanks to our successful badger vaccination appeal, Dorset Wildlife Trust is pleased to be able to start a vaccination programme on selected nature reserves in Dorset, to both protect badgers and support farmers,” he added.

Meanwhile, the RSPCA has been told it cannot use an anti-badger cull advert again which used the term “exterminate” to describe the Government’s cull trials.

The ad featured an image of a syringe and bullet at the top with a headline “Vaccinate or Exterminate?”

Tory MP Simon Hart, a former chief executive of the Countryside Alliance, was one of more than 100 people who complained to the Advertising Standards Authority, although three of the four grounds for complaint were dismissed by the advertising watchdog, it agreed the use of the word “exterminate” implied wrongly that every  badger in the cull area would be shot.

An RSPCA spokesman said: “The RSPCA welcomes the judgment by the ASA to dismiss three out of four of the areas of complaint about the advert. We respectfully disagree in relation to the one area of complaint that has been upheld.”

, , , , , , ,

5 Comments

Sing If You Are Glad To Be Gay

While Tom Robinson may be free to sing about being gay no one in India is, after a 2009 high court decision decriminalising homosexual behaviour was recently overturned, making the practice of homosexual behaviour punishable by up to ten years in prison (http://www.washingtonpost.com/world/court-in-india-criminalizes-homosexuality/2013/12/11/ea7274a6-6227-11e3-a7b4-4a75ebc432ab_story.html). This is one of the most insane things I have read recently. Does the Indian Supreme Court have nothing better to do with its time than interfere with people’s personal lives? I was unbelievably disappointed by this decision because I had really thought that as a society we had moved beyond such pettiness, although I should not have been surprised when being gay is still illegal in countries like Uganda. I fail to understand why homosexuality elicits such incredibly strong negative emotions. Why do people feel so threatened by what other people do sexually, especially as gay activity is extremely prevalent throughout the animal kingdom (apart from humans homosexuality has been described in black swans, gulls, mallards, penguins, dolphins, bison, bonobos, elephants, giraffes, the list goes on)?

Years ago a friend of mine decided to come out of the closet. He seemed quite disappointed by my non-reaction when he told me he was gay. I had, actually, worked it out years before. Although it sounds like a cliché, how many young men who never mention a girlfriend and live by themselves in an immaculately kept apartment are not gay? What did disappoint me slightly was the fact that he felt it necessary to tell me, as if the revelation of his sexual orientation would somehow alter our relationship. It was obviously a big issue for him but it was completely inconsequential to me. It is a pity that there appears to be such a stigma attached to a person’s sexuality that they feel the need to tell their family and friends about it, when they do not feel a similar need to reveal their religious affiliations. I would have reacted much more strongly if he had told me that he was a Collingwood supporter, as that would really have tested the friendship, me being a Carlton supporter. But being gay? Really, I could care less and don’t see why any of my friends should feel the need to tell me about it.

While we have made great strides in accepting people of varying sexual orientations we will not be truly civilised until gay people feel the same need to reveal their sexual orientation to others as non-gay people do. Unfortunately this ridiculous ruling in India demonstrates that that time is some way off yet.

Dr. F. Bunny

, , , , , , , , , ,

1 Comment

Two thousand mice dropped on Guam by parachute — to kill snakes

From: http://usnews.nbcnews.com/_news/2013/12/02/21724382-two-thousand-mice-dropped-on-guam-by-parachute-to-kill-snakes

Eric Talmadge / AP file

A brown tree snake on Andersen Air Force Base on the island of Guam in February.

They floated down from the sky Sunday — 2,000 mice, wafting on tiny cardboard parachutes over Andersen Air Force Base in the U.S. territory of Guam.

But the rodent commandos didn’t know they were on a mission: to help eradicate the brown tree snake, an invasive species that has caused millions of dollars in wildlife and commercial losses since it arrived a few decades ago.

That’s because they were dead. And pumped full of painkillers.

The unlikely invasion was the fourth and biggest rodent air assault so far, part of an $8 million U.S. program approved in February to eradicate the snakes and save the exotic native birds that are their snack food.

“Every time there is a technique that is tested and shows promise, we jump on that bandwagon and promote it and help out and facilitate its implementation,” Tino Aguon, acting chief of the U.S. Agriculture Department’s wildlife resources office for Guam, told NBC station KUAM of Hagatna.

It’s not just birds the government is trying to protect. It’s also money.

Andersen, like other large industrial complexes on the Western Pacific island, is regularly bedeviled by power failures caused when the snakes wriggle their way into electric substations — an average of 80 a year, costing as much as $4 million in annual repair costs and lost productivity, the Interior Department estimated in 2005.

The U.S. has tried lots of ways to eliminate the snakes, which it says likely arrived in an inadequately inspected cargo shipment sometime in the 1950s.

Snake traps, snake-sniffing dogs and snake-hunting inspectors have all helped control the population, but the snakes have proved especially hardy and now infest the entire island. Guam is home to an estimated 2 million of the reptiles, which in some areas reach a density of 13,000 per square mile — more concentrated than even in the Amazonian rainforests, the government says.

But brown tree snakes have an Achilles’ heel: Tylenol.

For some reason, the snakes are almost uniquely sensitive to acetaminophen, the active ingredient in the ubiquitous over-the-counter painkiller. If you can get a tree snake to eat just 80 milligrams, you can kill it. That’s only about one-sixth of a standard pill — pigs, dogs and other similarly sized animals would have to eat about 500 of the baited mice to get a lethal dose.

Brown tree snakes also love mice. It’s easy to bait mice with acetaminophen, but how do you then deliver the mice to the snakes?

“The process is quite simple,” Dan Vice, the Agriculture Department’s assistant supervisory wildlife biologist for Guam, told KUAM.

Helicopters make low-altitude flights over the base’s forested areas, dropping their furry bundles on a timed sequence. Each mouse is laced with the deadly microdose of acetaminophen and strung up to two pieces of cardboard and green tissue paper.

“The cardboard is heavier than the tissue paper and opens up in an inverted horseshoe,” Vice said. “It then floats down and ultimately hangs up in the forest canopy. Once it’s hung in the forest canopy, snakes have an opportunity to consume the bait.”

Wildlife workers do have a way to chart how well the mice work. In addition to the acetaminophen and the parachutes, some of the poison pests also come equipped with tiny data-transmitting radios.

, , , , ,

Leave a comment

More Sex Please

The following is a link to an article in Der Spiegel magazine: http://www.spiegel.de/kultur/gesellschaft/silke-burmester-ueber-sex-a-936386.html. Unfortunately the article is in German so, unless you are conversant with that language, you will have to trust my translation.

The basic thrust of the article is that sex is good for you. Having sex twice a week will boost your immune system by up to 60% and reduce your chances of catching a cold by up to 50%, compared with abstainers. Apparently a bout of sex will provide similar health benefits for your heart and cardiovascular system as a brisk two kilometre walk.

The article’s author then lists the numerous additional benefits that sex can provide:

  • Sex with international partners promotes international relations
  • Sex stimulates the economy (condoms, post-coital cigarettes, etc.)
  • Sex relaxes the mind and body
  • Sex decreases the frequency of migraines in women
  • Sex improves the complexion
  • Sex facilitates reconciliation
  • Sex requires minimal training
  • Sex produces children, also good for the economy
  • Sex improves memory
  • Sex burns calories
  • Sex reduces the incidence of stroke and heart attack in men
  • Sex promotes a feeling of well-being through endorphin release
  • Sex strengthens the bond between partners
  • Sex reduces the incidence of osteoporosis in women
  • Sex is a great way to meet new people

And, last but not least, sex drags you away from the computer. Bye.

Dr. F. Bunny

, , , , , , , , ,

Leave a comment