“That doesn’t look very scary. More like a six-foot turkey.”

One of the things I enjoy saying the most about my experience with wildlife rehabilitation is that I have worked with raptors – birds of prey like owls, hawks, and falcons. They are amazing, interesting birds but I’ll admit that part of that fun is that when people hear “raptor” they often imagine this:

This association is probably partly due to the blockbuster “Jurassic Park” and other dinosaur movies. A major theme of the film, and one that I love as a student of evolutionary anthropology, is demonstration of the bird-dinosaur relationship. The species Compsognathus is described as walking chicken-like, and the final scene of Jurassic Park shows a flock of birds flying from Isla Nublar and the dinosaurs that dwell on it. After Dr. Alan Grant is laughed at for stating that dinosaurs obviously became birds, he retorts with this:

“Well, maybe dinosaurs have more in common with present-day birds than they do with reptiles. Look at the pubic bone: turned backward, just like a bird. Look at the vertebrae: full of airsacs and hollows, just like a bird. And even the word ‘raptor’ means ‘bird of prey.’”

However, this quote implies that there was foresight in the naming of both birds of prey and certain dinosaurs “raptors” because birds are the evolutionary descendants of some dinosaur species. But the way in which language evolves through translation and interpretation means one cannot assume that the naming intentional. And in terms of the history of the knowledge of evolution, this naming was actually more of a coincidence.

The word “raptor” comes from a Latin verb rapere “to seize by force”. Birds of prey are called raptors because of they way they hunt, seizing their prey out of the air, and Websters dictionary first defined birds of prey as raptors in 1823.

The term “velociraptor”, and other species containing the suffix -raptor, probably originated in scientific literature around 1924. They were so named because velox means “swift” and so velociraptors were thought to be speedy predators who seized their prey.

However, both of these groups received their designation as “raptor” long before paleontologists were able to link birds as the descendants of dinosaurs. The evidence of the bird-dinosaur evolutionary lineage was not concretely supported until the 1980s when dinosaur phylogeny was more fully understood with increasing knowledge of genetics, phylogeny, and evolution.

Assuming that the two share a name because they share an ancestor is a false cause logical fallacy, meaning that a false assumption is made when one believes a relationship seen between two things automatically implies one caused the other.  In fact birds of prey and some dinosaur species were named before their evolutionary relationship was understood and so their name was more a convenient coincidence of word choice.

If early orinthologists had decided that birds of prey didn’t seize their prey but rather grabbed, snatched, clasped, clutched, or caught them, the Latin translation never would have matched the dinosaur term that came later.

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“Diets, like clothes, should be tailored to you”

Fad diets, as their name suggests, are easy-to-follow and trendy diets focused more on short-term success than long-term maintenance of health and weight. Focus is usually placed on eliminating or emphasizing a particular food group for health benefits.

However these diets tend to be difficult and sometimes even dangerous to follow for long periods of time. The Paleo Diet is considered by many to be a fad diet, which I why I was surprised that it is still a somewhat prevalent.

The Paleo Diet, short for Paleolithic Diet, is based on the diet of the early humans (called hominids) which lived during the Paleolithic era of 2.5 million years ago to 10 thousand years ago. It is believed to follow the general “ancestral human diet”.

It claims that humans are most adapted to the diet of their Paleolithic ancestors – fish, eggs, vegetables, fruits, roots, nuts, and wild game. Therefore sugars, salts, oils, and grains and vegetables which came about during the Agricultural Revolution are discouraged.

The claim of the Paleo Diet is that natural selection has not strongly acted on humans since the rise of agriculture, thus humans are maladjusted to the modern diets which they now consume. Hunter-gatherer societies, which still follow the basic ancestral human diets, have overall lower prevalence of disease.

By this reasoning, foods which humans are considered ill-adapted for are partly responsible for the increasing rates of obesity, cardiovascular disease, high blood pressure, Type 2 diabetes, and even cancer.  To help avoid the diseases caused by the “modern affluent diet”, humans should follow the Paleo Diet and avoid modern foods.

But, while abstaining from excesses of sugar and oil is beneficial to human health, the actual scientific reasoning behind the Paleo Diet is shaky at best.

1. Lifestyle is a major factor in any diet, not just the Paleo Diet

The lifestyle that the Paleo Diet promotes is itself healthy – growing or hunting one’s own food, and not eating in excess are healthy additions to any diet protocol.  The main bulk of the health advantages stemming not from what hunter-gatherer peoples actually eat, but how they live, and their diets are a result of their culture.

Basically, hunter-gatherers are more active and tend to consume fresher foods because they must acquire it for themselves.  Any modern American who hunts and gathers their own food will surely already lead a more active lifestyle and is also less likely to consume processed foods and junk food, whether or not they are following the textbook Paleo Diet.

However, the changes that have occurred among urban societies, even in the past century or so, have made following a hunter-gatherer lifestyle next-to-impossible.

2. The Paleo Diet assumes human evolution abruptly stopped at the rise of agriculture

The assumption that humans have not changed or adapted to their environment in the past 10,000 years ignores everything we know about evolutionary change. If adaptation comes naturally over time, why should change suddenly stop? While it is true that natural selection may be acting less on populations now with modern medicine and more consistent food sources, but fluctuations in population genetics are always present.

Furthermore, there is evidence that rapid changes have occurred in human populations since the rise of agriculture, and the evolution of lactose tolerance is a good example. A few thousand years ago there was an increased interest in animal husbandry in human populations, which led to more access to dairy products like cheese and milk. Early humans naturally lost lactose tolerance after weaning, but populations with access to dairy have since evolved a genetic ability to continue to digest lactose into adulthood and therfore retain the ability to acquire nourishment from dairy products.

3. Humans are opportunistic omnivores and are designed to eat a variety of diets

The premise of the Paleo Diet is that humans are specifically adapted to a certain diet and are maladjusted to consuming different diets, which has already been proven false by the evidence of change in lactose tolerance. Furthermore, this assumes that all early human groups ate the same diet, which is wildly blind to the fact that human populations arose all over the world and couldn’t possibly have eaten the same foods. And anthropologists can never be sure of the exact diet of any ancient group because it would have been widely variable based on location, season, and food availability.

Furthermore, the fact that humans only had access to certain foods during their evolutionary history doesn’t automatically mean that they aren’t capable of eating other things.

4. Diet alone cannot guarantee health

There is no specific relationship between genotype (one’s genes) and phenotype (one’s physical traits), so even if humans were specifically adapted for a certain diet, genes are not the only factors which influence final health, and environment and early development can have equally strong impacts later in life.  Hormones, musculature, and metabolism, among other factors, mean that some people will naturally weigh more or less no matter the diet they follow.

So, while the reasoning and science behind the Paleo Diet seems inaccurate at best, this isn’t to say that it can’t be beneficial to one’s health to follow some of the suggestions it makes. However, strictly following the Paleo Diet based on the belief that you are eating as ancestral humans did won’t be anymore beneficial than any other fad diet out there.

“If we can teach people about wildlife, they will be touched”

Out of genuine interest rather than any particular career planing, I spent this past summer working an internship at Avian Wildlife Center that rehabilitates and releases injured wild birds, anything from hummingbirds to herons. Most of the birds we dealt with were brought to us after unfortunate interactions with humans in some way – nest disrupted, hit by car, poisoned by pollution, etc. At the center, birds receive care until they can be released back into the wild.

3 little victims of an illegal nest removal, these fledgling American Robins are a few weeks away from release back into the wild

3 little victims of an illegal nest removal, these fledgling American Robins are a few weeks away from release back into the wild

Before release they are also tested for parasites, ability to self-feed, and feather condition.  During their time at the center people interact with them as little as possible so they don’t learn to associate humans with food and approach them after being released.

It’s a great and rewarding job, if you aren’t expecting high pay, flexible hours, or a stress-free work environment. It’s also pretty interesting, and I could (and did) leave work every day with multiple bird stories to share.

This baby Sandhill Crane was everyone's favorite, and an opportunity to take charge of the hand-feeding was a contested role during his visit.

This baby Lesser Sandhill Crane was everyone’s favorite, and an opportunity to take charge of his bi-hourly hand-feeding routine was a contested role during his visit.

One particularly interesting case we had was a lady who brought in a fallen sparrow nest, with three baby birds. She commented that she was surprised one of the babies was twice the size of the other two.  This is because one wasn’t a sparrow at all, but a cowbird. They are incredibly interesting birds, particularly in how they raise their young – they don’t. Instead, they are nest parasites: the mother cowbird flies around laying eggs in other birds nests to be raised by an unsuspecting parent bird, in this case a sparrow.

A juvenile Brown-headed Cowbird being fed by its foster parent, a Chipping Sparrow, in Baltimore Co., Maryland (6/5/2011). Photo by Jon Corcoran (http://www.flickr.com/photos/thrasher72/).

A juvenile Brown-headed Cowbird being fed by its foster parent, a Chipping Sparrow, in Baltimore Co., Maryland (6/5/2011). Photo by Jon Corcoran (http://www.flickr.com/photos/thrasher72/).

The lady, who before this information had been impressed by his advanced growth, was suddenly appalled at the poor little cowbird in her sparrow nest. She then asked if we would euthanize the “parasite” since it disrupted the life cycles of the other birds. Of course that is not the case, and we explained that we would take care of it just the same – the center takes any injured wild bird, irregardless of how many individuals of that species they might already have because it makes no attempts to influence natural population ratios.

She wasn’t convinced why it should be saved, which was a common sentiment among several of the rescuers of cowbirds we spoke to over the summer.

Perhaps the term “parasite” gives them a bad reputation, but cowbirds are truly fascinating. Where most other species would imprint on whatever they first see – imagine the classic example of a baby duckling who imprints on a human when it hatches and spends its day following people instead of fellow ducks. Cowbirds, however, are smart enough to know what they are without having to see another cowbird during their whole infancy.  This is because they recognize their own coloration and use that information to find mates in the future.

Though barely related, I had to include this image of 2 ducklings imprinted to a Corgi

Though barely related, I had to include this image of 2 ducklings imprinted on a Corgi

Generally, to the public we simply try to explain that it is the bird’s natural behavior which should not be tampered with. Cowbirds are not an invasive species and are completely meant to coexist with other birds in their natural habitat, which ranges all across North America from southern Canada to southern Mexico.

They can’t thrive without this method of reproduction, which arose naturally through co-evolution with competing bird species.  It is simply how they live and reproduce, and the individual should not be blamed for its innate biological behavior, any more than a hawk should be blamed when it kills a dove for its dinner.

This isn’t to say that cowbirds don’t harm other birds – I am sure that unknowingly raising a baby cowbird takes its toll on a sparrow mother, who will be half the size of her baby before it leaves the nest. But they don’t outright kill their hosts (a good parasite doesn’t kill its host, or it loses its livelihood), and the parents with whom the cowbird tries to leave her eggs are not completely defenseless in the matter, as they sometimes detect and eject foreign eggs.

Cowbirds are known to parasitize over 100 different species, so their eggs seldom match those they are laid with.

Cowbirds are known to parasitize over 100 different species, so their eggs seldom match those they are laid with.  Here, a large speckled cowbird egg is alongside 3 smaller blue Chipping Sparrow eggs.

Still, there is so much love (and funding to care for) birds of prey, who must kill to consume at least 20% of their body weight a day to sustain themselves. People marvel over the beauty of an eagle soaring in the sky while nest parasites, such as cowbirds, cuckoos and several other species, are met with animosity – even though they are usually not responsible for the deaths of any other birds and are equally fascinating creatures.

  • (An exception is if a cowbird egg/baby is discovered and tossed from the nest by the duped parent. A response, nicknamed the “Mafia Behavior”, occurs where the mother cowbird will return to the nest and destroy the other eggs, in hopes of forcing the victim to create a new nest and lay a new brood, also giving her another chance to lay new eggs).

Cowbirds are somewhat infamous for contributing to the near extinction of the Kirtland’s warbler and there were even several mass attempts to remove cowbird eggs from warbler nests, although later it was found there were several other factors leading to their decline besides cowbirds, mostly from human damages to the ecosystem. And studies have even shown that when humans try to remove cowbirds, we end up helping them – removing birds from an area signals less competition, so they are able to reproduce more in that area and end up parasitizing even more nests than they would normally would have.

As with any animal that makes its way through life by competing with others, there are winners and losers.  As a rehabilitator, helping one means eventually harming another, as the circle of life continues in the wild and someone must be preyed or parasitized upon. That doesn’t mean efforts to protect the environment are any less meaningful and perhaps the best thing we can do is try to fix the damages done by humans and restore the balance that existed before human activity began to cause serious disruptions.

After all, these species got along just fine before humans showed up to observe, monitor, and “fix” nature.

“If you’re short of trouble, take a goat.”

This gif was circulating reddit a few weeks back and I thought it was pretty awesome so I did some more research on the subjects of the image, Fainting Goats:

A fainting goat is a variety of goat that experiences loss of muscle control and “faints” when it feels panic. Anyone with some free time should search out more Youtube videos of them in action (or rather, inaction).

Since fainting in the face of danger is an extremely disadvantageous trait to have in the wild, these goats are only found in domestic populations and fainting goats, also called myotonic goats, are actually bred to have this unique trait.

Beccause they are so unique, they are actually identified as their own species, though they are really just a variety of the common domestic goat. The first examples of them were recorded in the late 1800s and it seems that farmers were so amused by them they purposely bred them.

All colors and patterns of them exist, just as in regular populations. They are typically kept as pets and farmers find them easy to care for because they have difficulty escaping – the excitement of jumping a fence usually causes them to faint.

All fainting goats have a condition known as myotonia congenita, or Thomsen’s disease. The exact cause of the condition is unknown, though it is highly suspected to be the result of defective chloride channels in the muscle fiber or a deficiency of acetylcholine. Chloride ions and acetylcholine are both molecules necessary for proper muscle function by causing the muscles to contract – the molecules are released into muscle fibers and the muscles contract.

After they flex, normal muscles release the molecules back out through channels in the muscle fiber.  However, when panicked the muscles of individuals with myotonia congenita cannot release the molecules right away, causing a prolonged muscle contraction where the muscles cannot relax.

With this condition, panic causes the muscles the tense, however they do not relax as quickly as they should, resulting in a 10-20 second lapse where the animal’s muscles are frozen. They never actually lose consciousness. Nor do they feel pain with this condition – an explanation that breeders often cite when confronted by animal rights activists concerned with the intentional breeding of goats with the disorder.

Also, usually the older goats learn to associate panic with “fainting” and learn to brace themselves or lean up against something to prevent falling.

Still, though some are able to somewhat control their behavior, they only exist because humans love having them as pets. In the wild, this trait would never be passed on to a new generation because any individual that faints in panic would surely be the first prey to a predator. (This also contributes to another older use for fainting goats – for the protection of more valuable members of a herd. Often in predator-prone areas, fainting goats are kept alongside sheep so that if the flock is attacked by wild animals, the sheep will escape while the goat faints and does not escape.)

But for the most part, this species of goat is kept for its amusing behavior, and there are even festivals down south that honor the unique genetic situation that results in fainting goats.

“If you’re short of trouble, take a goat.”
~ Finnish saying

“If all your other friends jumped off a bridge, would you?”

If you have ever heard of lemmings, you will probably imagine those little fluffy rodents that are pretty stupid and commit mass suicides by jumping off cliffs. Their tragic story has become synonymous with blindly following a crowd, and their sad fate demonstrates the moral of any story beginning with the classic parental question of if all your other friends jumped off a bridge

Except that lemmings don’t actually gather into little fluffy lemming herds to hurl themselves off cliffs. (Disney filmographers did that once though, but we will get to that later.)

So imagine my surprise when sitting in my “Psychology of Animal Behavior” class the other day, I hear my professor use mass suicides in lemming populations as an example of a coordinated group behavior. Whoa. Whoa. Whoa. My animal behavior professor did not just actually tell his class this right? I was shocked that he would use this as an example, and if he was just using it symbolically, not everyone in the class understood his humor.

So here it is: Lemming mass suicides are false. They don’t jump off cliffs to icy waters of death. They just don’t.

But the incorporation of this myth into modern-day belief is a pretty interesting story involving a nature documentary that apparently wasn’t interesting enough for the general audience without fabricating odd animal behavior (which is a sad fact if filmographers felt they needed to jazz up the wonders of nature).

In an effort to prove my professor wrong (which I enjoy far too much sometimes), I started googling and this was the best site I found: Great Moments in Science.  I took the liberty of summing up my findings below:

FACT: The 1958 Disney documentary “White Wilderness” was meant to be an accurate nature documentary filmed in Canada. It features lemmings migrating across an open tundra, then plunging to their deaths in icy rivers in a coordinated manner. The film treats this behavior as scientific fact and incorporates it nicely into the rest of the documentary about tundra wildlife.

MYTH: Lemmings are not from the region where the film was made, they were in fact brought there by the filmographers, and filmed on a snow-covered turntable to look as though they were on a massive trek across the tundra. Then a small handful of them were herded off the turntable right into a river, creating the illusion of a mass suicide. (PETA wasn’t founded until 1980, otherwise I’m guessing they would have had a strong opinion on this matter.)

This film, along with the public’s general lack of knowledge at the time, led to the spread of the myth of lemming suicides which is still a part of our culture. To be fair, the film crew (probably unknowingly) picked a good animal to perpetrate strange behavior for: there was already a medieval Nordic myth that they spontaneously generated and fell from the sky during storms. (Which, just saying, flying lemmings set against a back-drop of thunder and lightning would have made for a much more epic documentary scene – if I would good at Photoshop you would also get to enjoy this imagery, but alas, I’m not.) In light of an increase in scientific understanding, later myths acknowledged that lemmings were not created through spontaneous generation, so any in the sky were a result of wind.

All that being said, the filmographers likely based their ideas on the scientific fact that in high population surges, migrations can be dangerous for lemmings and some are bound to die by being pushed, crushed, or drowned by the sheer weight of other lemmings. So according to population dynamics, the myth has a basis of fact in that migrations can be dangerous, but with a large, large flair of artistic license.

 (I had to include this, I freaking love Gary Larsen’s Far Side comics)

And thus concludes this rant.

*Also, just an additional note: Although I have never actually seen the film, I really want to and it apparently is “visually stunning” and “one of Disney’s best documentaries” (I’m not sure what this means for Disney’s other documentaries like “Chimpanzee”, “Big Cats”, or Babies”). And it even won an Oscar for “Best Documentary” in 1960.  More info here: http://www.imdb.com/title/tt0052389/

What’s coming soon:

So what is this cool place? What makes it famous?  Coming Soon!