Category Archives: Animals

Another Bee Study Finds CCD is Likely Due to Combination of Factors Including Pesticides

Abstract of open access science paper funded by the United States Department of Agriculture (USDA) Crop Pollination Exposes Honey Bees to Pesticides Which Alters Their Susceptibility to the Gut Pathogen Nosema ceranae:

Recent declines in honey bee populations and increasing demand for insect-pollinated crops raise concerns about pollinator shortages. Pesticide exposure and pathogens may interact to have strong negative effects on managed honey bee colonies. Such findings are of great concern given the large numbers and high levels of pesticides found in honey bee colonies. Thus it is crucial to determine how field-relevant combinations and loads of pesticides affect bee health.

We collected pollen from bee hives in seven major crops to determine 1) what types of pesticides bees are exposed to when rented for pollination of various crops and 2) how field-relevant pesticide blends affect bees’ susceptibility to the gut parasite Nosema ceranae. Our samples represent pollen collected by foragers for use by the colony, and do not necessarily indicate foragers’ roles as pollinators. In blueberry, cranberry, cucumber, pumpkin and watermelon bees collected pollen almost exclusively from weeds and wildflowers during our sampling.

Thus more attention must be paid to how honey bees are exposed to pesticides outside of the field in which they are placed. We detected 35 different pesticides in the sampled pollen, and found high fungicide loads. The insecticides esfenvalerate and phosmet were at a concentration higher than their median lethal dose in at least one pollen sample. While fungicides are typically seen as fairly safe for honey bees, we found an increased probability of Nosema infection in bees that consumed pollen with a higher fungicide load.

Our results highlight a need for research on sub-lethal effects of fungicides and other chemicals that bees placed in an agricultural setting are exposed to.

The attempts to discover the main causes of bee colony deaths and find solutions continues to prove difficult years after the problems became major. The complex interaction of many variables makes it difficult. And special interest groups pushing pesticides and the like, which have seemed to be major contributors to the problem for years, make it even more difficult (by preventing restrictions on potentially damaging pesticide use).

The challenges in determining what is killing bees are similar to the challenges of discovering what practices are damaging human health. The success of studying complex biological interactions (to discover threats to human health) is extremely limited. I am concerned we are far too caviler about using large numbers of interventions (drugs, pesticides, massive antibiotics use in factory farms, pollution…).

Tropical Lizards Can Solve Novel Problems and Remember the Solutions

Brainy Lizards Pass Tests for Birds

[Duke biologist Manuel Leal] tested the lizards using a wooden block with two wells, one that was empty and one that held a worm but was covered by a cap. Four lizards, two male and two female, passed the test by either biting the cap or bumping it out of the way.

The lizards solved the problem in three fewer attempts than birds need to flip the correct cap and pass the test, Leal said. Birds usually get up to six chances a day, but lizards only get one chance per day because they eat less. In other words, if a lizard makes a mistake, it has to remember how to correct it until the next day
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Leal’s experiment “clearly demonstrates” that when faced with a situation the lizards had never experienced, most of them were able to devise a way to solve the problem. Their ability to “unlearn” a behavior, a skill that some mammalian species have difficulty in, is the mark of a cognitively advanced animal, said Jonathan Losos, a biologist at Harvard who was not involved in the study.
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To see if the lizards could reverse this association, Leal next placed the worm under the other cap. At first, all the lizards bumped or bit the formerly lucrative blue cap. But after a few mistakes, two of the lizards figured out the trick. “We named these two Plato and Socrates,” Leal said.

It is very cool to see what scientists keep learning about animals.

Scientific Inquiry Process Finds That Komodo Dragons Don’t have a Toxic Bite After All

This articles is another showing the scientific inquiry process at work. Scientists draw conclusions based on the data they have and experiments they do. Then scientists (sometimes the same people that did the original work) seek to confirm or refute the initial conclusions (based on new evidence or just repeating a similar experiment) and may seek to extend those conclusions.

Sometimes the scientists conclude the initial understanding was incorrect, such as with Komodo Dragon’s: Here Be Dragons: The Mythic Bite of the Komodo

for centuries Komodos have been feared by many, with tales of their deadly bite echoing through local cultures. It’s even thought the monstrous lizards may have inspired the mythical beasts that share their name. Their villainous reputation only grew when these fearsome predators were discovered by Europeans in the early twentieth century. But of all the terrible tales told about these dragons, none has been so persistent and pervasive than that of their bite. The mouths of Komodos are said to be laden with deadly bacteria from the decaying corpses they feed on, microbes so disgustingly virulent that the smallest bite lethally infects prey. As the story goes, Komodos have turned oral bacteria into a venom.

It’s a truly fascinating way for an animal to feed — well, truly fascinating in that it’s not true at all.

Homing Pigeons May Use Low Frequency Sound Maps To Locate Home

Mystery of Lost Homing Pigeons Finally Solved

Prior research had shown that birds hear incredibly low-frequency sound waves of about 0.1 Hertz, or a tenth of a cycle per second. These infrasound waves may emanate from in the ocean and create tiny disturbances in the atmosphere. Hagstrum began to think the birds used infrasound for navigation.
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on the odd day when the birds reached home from Jersey Hill without problems, the infrasound traveled between the two locations. At the other locations where pigeons headed off in the wrong direction, he showed that wind currents channeled the infrasound waves in that direction.

The explanation may solve other mysteries about pigeons — for instance, why they circle around before heading off in one direction. Because the sound waves are so long, but the birds’ ear canals are tiny, they need to circle to reconstruct the wave and figure out which way they are oriented, he said.

More interesting scientific inquiry. It is very interesting to learn what scientists are learning about our world – even when the conclusions are still preliminary and may be adjusted or refuted.

Parrots Given “Names” by Their Parents and Use Them Throughout Their Lives

Parrots learn their ‘names’ from their parents

Parrots, which have long amused us for their ability to imitate our vocal patterns, actually learn to caw their “names” from their parents, says a new Cornell study. The research offers the first evidence that parrots learn their unique signature calls from their parents and shows that vocal signaling in wild parrots is a socially acquired rather than a genetically wired trait.
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Previous research had shown that all wild parrots use unique “contact calls” that not only distinguish each bird individually, but also communicate their gender, and the mate and larger group they belong to.
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“Parrots can have extremely long periods [leading up] to independence, and this is thought to be related to their large brains,” explained Berg. The same goes for primates, he said, with humans in particular being “off the charts” when it comes to a lengthy stage of child dependence.

More research is required, to better understand the evolution of and interaction between these physical and behavioral traits, he said. “We still don’t have good explanations of how these behaviors help wild individuals survive and reproduce in nature,” he said.

The paper offers some possible explanations: Perhaps the parrots’ far-ranging journeys to “communal foraging sights” are what impress upon each parent the need to have their fledglings’ names sorted out — not unlike human parents’ need to call for their children by name at a crowded fair.

I enjoy learning more fun and cool stuff about the animals we share the world with. They are quite an interesting bunch of creatures.

Friday Fun: Gibbon Plays with Tiger Cubs

While this gibbon appears to be playing with the tiger cubs I am not sure the tigers see it as play.

Cancer Cells in Blind Mole Rats ‘commit suicide’

Cancer cells in blind mole rats ‘commit suicide’

Blind mole rats don’t get cancer, and geneticists have worked out why — their cells kill themselves with a poisonous protein when they multiply too much.

Blind mole rats, which live in underground burrows throughout Southern and Eastern Africa, and the Middle East, are fascinating creatures. The naked mole rat, in particular, is the only cold-blooded mammal known to man, doesn’t experience pain, and is also arguably the only mammal (along with the Damaraland mole rat) to demonstrate eusociality — that is, they live in large hierarchical communities with a queen and workers, like ants or bees.

They’re also cancer-proof, which was found in 2011 to be down to a gene that stops cancerous cells from forming. The same team thought that two other cancer-proof mole rat species might have similar genes, but instead it turns out that they do develop cancerous cells — it’s just that those cells are programmed to destroy themselves if they become dangerous.

Very interesting research. The results of evolution are amazing. And while turning the medical research discoveries into workable treatments for people is very difficult the continued increase in our knowledge helps us find treatments that work.

Add Over-Fishing to the Huge Government Debt as Examples of How We Are Consuming Beyond Our Means

Fish are hidden under the water so the unsustainable harvesting isn’t quite as obvious as the unsustainable government debt but they both are a result of us living beyond our sustainable production. You can live well by consuming past wealth and condemning your decedents to do without. That is the way we continue to live. Over-fishing a century ago was not as obviously dangerous as it is today. But we have witnessed many instances of overfishing devastating the fishing economy (when the fishing is unsustainable the inevitable result is collapse and elimination of the vast majority of the food and income that previous generations enjoyed).

The normal pattern has been to turn to more aggressive fishing methods and new technology to try and collect fish as over-fishing devastates yields. This, of course, further devastates the state of the resources and makes it so recovery will take much much longer (decades – or more).

New research shows the existing problems and the potential if we apply science and planning to manage fisheries effectively.

Using new methods to estimate thousands of unassessed fisheries, a new comprehensive study provides a new view of global fish stocks. The results show that the overall state of fisheries is worse than previously thought. Unassessed stocks, which are often left out of global analyses because of a lack of data, are declining at disturbing rates. When these fisheries are taken into account, the results indicate that over 40 percent of fisheries have crashed or are overfished, producing economic losses in excess of $50 billion per year.

The good news is that this decline is not universal: fisheries are starting to rebound in many areas across the globe and we can learn from these examples. Recovery trends are strongest for fisheries where data on the status of the fishery exists, and in which managers and fishermen have made science-based decisions and stuck with them in the face of political pressure.
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The amount of fish brought to shore could increase 40 percent on average – and double in some areas – compared to yields predicted if we continue current fishing trends.
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The management solutions to overfishing are well known, tested and proven to work. While these solutions are not “one-size-fits-all” for fisheries, there are common themes. Specifically, managers and fishermen must: 1. Reduce fishing to allow stocks to rebuild; 2. Set catches at a sustainable level that is based on the best available scientific and economic information rather than short-term political pressures; and 3. Prevent dangerous fishing activities that destroy habitat, wildlife, or breeding fish.

The over fishing problem is difficult because our nature is to ignore problems that are not immediate. But the costs of doing so are very large. If we don’t behave more wisely our children will pay the price. And, in fact, this problem is so acute now that those of us that expect to live a couple decades can expect to pay the price. In rich countries this will be tolerable, a bit less fish at much higher prices. In rich countries food prices are a minor expense compared to the billions of those not living in rich countries. They will suffer the most. As will those that have jobs directly dependent on fishing.

The Science Behind Hummingbird Flight

Aerodynamics of the hovering hummingbird

Hummingbirds and insects have evolved for sustained hovering ï¬‚ight from vastly different ancestral directions, and their distinct phylogenies underlie the differences in their aerodynamic styles. In all other birds—and, presumably, hummingbird ancestors—the downstroke provides 100% of weight support during slow ï¬‚ight and hovering. Given that many birds possess the mass-speciï¬c power (using anaerobic metabolism) to hover for short periods, the selective pressure on hummingbird ancestors was probably for increased efï¬ciency (resulting in stiff wings with greatly simpliï¬ed
kinematics), and an upstroke muscle (the supracoracoideus) that makes the recovery stroke rapid, while contributing enough to the hovering power requirements to allow the downstroke muscle (the pectoralis) to operate within its aerobic limits.

In other words, this pseudosymmetrical wingbeat cycle is good enough, and although hummingbirds do not exhibit the elegant aerodynamic symmetry of insects, natural selection rewards ‘good enough’ as richly as it does our aesthetic ideals

Great Webcast Explaining the Digestive Systems

You will learn things like why it is so important to chew your food well (increase the surface area for enzymes to get at the food). Our bodies also have adapted to provide a huge surface area for the digestive system to work; the small intestine alone has a surface area of 250 square meters (larger than the size of most apartments). Your small intestine is 4.5 to 10.5 meters long.