How To Get Into An Animal Behavior Graduate Program: Deciding Where to Apply

Is the idea of grad school stressing you out?
Image by freedigitalphotos.net.

If you are contemplating applying to graduate school in scientific research, the choice of where to apply can feel overwhelming. Each scientific field can be broken down into countless sub-fields. Each sub-field has countless researchers studying countless topics. How do you know which to choose? What if your choices pigeon-hole your career before you even get it off the ground? What schools have the best programs? What if the schools I choose are too competitive for me to get into? Although these are legitimate concerns, choosing graduate programs to apply to doesn’t have to be so stressful… and it can even be fun.

As with most everything, the earlier you start your planning, the less stressed you will be when the time comes to act. As soon as you realize that you are considering graduate school for research, start a list of possible labs you may want to work in. This list should include: possible mentors, the universities and departments they are affiliated with, the topics they study, and the techniques they use. Later, as you start to narrow your list, you may also want to include information such as: where the school is located, financial support offered, the minimum GPAs required, test scores required, courses required and application due dates.

For many of us scientific researchers, the realization that we wanted to pursue research as a career came from the inspiration we got from discovering a particular study or scientific story. The source of your inspiration is a great place to start. Look up the study that inspired you and other similar studies by some of the same authors. Often, the head of the research lab (called the Principal Investigator or P.I.) is the last author listed in the research paper. The paper should also mention what university and department each author is affiliated with. Now, armed with names of researchers and schools, start web-surfing and filling in the details on your list. If you find other interesting papers, researchers, or schools, allow yourself to follow the leads and add to your list. Keep an open mind during this stage: Most researchers study a range of research topics that they often list on university-affiliated or personal websites; If you are interested in animal behavior, you could pursue a degree in Animal Behavior, Biology, Zoology, Ecology Evolution and Behavior, Psychology or even Neuroscience; And try not to eliminate any programs based on geography unless you know in your heart that if it were the only program to accept you that you still would not go. By the end of this process, if you have a list of 15-20 possible labs to apply to, you should be in good shape.

Once you have a list of possible labs, it is time to narrow down your list to the 6-12 labs you will actually apply to. Here are some factors to consider:

1. The most important factor in graduate student success is whether you can work well with your advisor. Some labs will list current or past lab members on their webpages. If you can find email addresses, email some lab members to get their opinion of the P.I.’s abilities as a mentor. You can also ask faculty members at your university or use social media sites such as Facebook or LinkedIn to find out if any of the potential advisors you are interested in has a reputation.

2. Look up each researcher’s publications and webpages to get a sense of that person’s past and present research topics. Obviously, it is important to find a research topic that can keep you interested for the 4-8 years that it will take you to complete your degree. If you are considering a career in academia, it is also important to consider the techniques that you may learn from a lab. Unfortunately, animal behavior research techniques alone are not very marketable to research labs looking for a Postdoc or Research Scientist, in part because it is hard to obtain grants for studying animal behavior alone. A combination of animal behavior techniques with techniques in physiology, ecology, or evolution will make you much more employable when you complete your degree.

3. The rank or reputation of the school may contribute to your marketability when you complete your degree. There are some reputable graduate program rankings, such as U.S. News and World Report’s annual ranking of schools. Their ranking of graduate programs in biology can be found here. You can also get a sense of a school’s reputation by the number of publications from faculty in the program in a given year. Again, faculty at your current school and social media sites can be helpful with this insight as well.

4. Most graduate programs in animal behavior offer financial support in the form of teaching assistantships (T.A.s) and research assistantships (R.A.s) that cover tuition, healthcare, and provide a stipend. However, the availability, pay, and time commitment of these positions are not always equal. Contact the departments you are interested in to find out what kind of financial support they provide to their graduate students and how reliably available the positions are.

5. The location of the school may be important to you, as you will live in this place for the 4-8 years that it takes you to complete your degree. However, you won’t get out much once you start your program, so it really doesn’t matter where you are anyway.

6. If you are concerned about your GPA, GRE scores, or lack of coursework, you can sometimes find minimum requirements for a program on their website. You can also call departments and ask.

Good luck and have fun with your list!

And for more advice on applying to graduate programs, go here.

Caught in My Web: Memory Regeneration, Fish Sex, and the Physics of Swimming

For this edition of Caught in My Web, we explore the science of swimming and other underwater oddities.

1. If you are pondering great questions in life, such as "How is swimming different between a sperm and a sperm whale?", then you are in luck. The physics of how size influences the ability to swim is explained by Aatish Bhatia on TEDEd.

2. Neil Hammerschlag, a shark scientist and blogger for National Geographic, discusses the use of satellite tags for shark research.

3. Phys.org explains the science of side-to-side fish movement.

4. Robert Krulwich at NPR talks about headless planarians that regenerate their heads and their memories.

5. And the Beckman Institute tells you why Nemo would have become a girl if he had not found his dad:

Science Beat: Round 3

Sometimes science just makes more sense with a beat. Last January, I shared with you some fun music videos on fish genetics, climate science, and sexual reproduction. In Round 2, we saw music videos on the periodic table, cellular respiration and muscles. Here are the competitors for Round 3:

Cellular Biology:

Anatomy and Physiology:

Taxonomy:

Vote for your favorite in the comments section below and check out other sciency song battles at Science Song Playlist, The Science Life, Science Beat and Science Beat: Round 2, Scientist Swagger and Battle of The Grad Programs!

And if you feel so inspired, make a video of your own, upload it on YouTube and send me a link to include in a future battle!

The Truth Behind Those Sleeping Bears (A Guest Post)

By Tabitha Starjnski-Schneider

Name some animals that hibernate.

Was the first one mentioned a bear? That’s understandable…you were probably told that bears go to sleep shortly before winter, stay asleep the entire winter, and wake up in early spring.

What if I told you that your teachers lied to you, and that bears don’t actually hibernate?! Not a true hibernation, at least.

For an animal to be considered a true hibernator, it actually needs to stay in a sleep state for months at a time (like during an entire season), but also lower its body temperature far below where most other animals barely survive. Such an animal thus hibernates by lowering its metabolism, dropping its body temperature, and passing, most commonly, much of the winter in this Rip Van Winkle state. The many challenges of enduring a long and strenuous season such as winter, while "sleeping" it away, are complicated, but here we talk about just a couple.

Something your teacher may have also told you was that bears are mammals, and therefore are "warm-blooded". That seems a little silly; all animals with blood are going to have warm blood. Bears are actually called endothermic, meaning they don’t have to rely on warming or cooling their bodies by outside forces such as the sun. While undergoing this sleep-state, bears possess internal and external temperature control. These animals slightly lower their heart rate and body temperature internally and minimize their external movements in an effort to save energy and conserve heat. Of course these periods of reduced heart rate, temperature and inactivity don’t actually last all winter, as with true hibernation, but only a few weeks at a time. This overall ability and state is called torpor, not true hibernation. And although there is debate over the definitions of each, most researchers believe there is enough of a difference to categorize them separately (like cat naps versus comas).

One of the reasons for taking these naps is as basic as why we grocery shop. When the environment changes in such a way that doesn’t suit an animal (i.e. an empty fridge), they can better survive by conserving energy and going inactive until food returns. Before napping however, each adult bear will begin to dig a den, hollow out a tree trunk, and/or find a cave to prepare for winter. Once tucked away in their little beds, they use these dens like a Thermos, retaining as much of their body heat as possible. For the most part, these giants go to sleep for a few weeks at a time, wake up to warm their bodies some, then fall back asleep. This occurs over the course of a winter season until spring arrives and the bear can reemerge into the re-warmed world outside.

There is another, more important reason why these bears slumber though. After breeding in spring/summer, these mammals begin their fall-time buffet, eating foods high in carbohydrates and fat to gain as much weight as possible. Why you ask? So that the mothers gain enough fat and energy to develop, birth, and feed their young while in the winter hideaways. Ever see the videos of polar bears emerging with their cubs from a snowy fortress in the side of a hill?

Now how could they ever give birth if they were sleeping the whole time? It’s the same with black bears and grizzly bears, for that matter.

It all sounds pretty cool right? These mama bears should be given a medal for their dedication. And the next time someone refers to bears hibernating, you can assuredly respond that they actually enter a state of torpor, or winter-long cat naps.

Crocodilians Hunt With Tools!

A crocodile lures in birds with sticks that would make a nice nest.
Photo by Dinets published in Ethology, Ecology & Evoluton 2013.

What would happen to mankind if crocodiles and alligators were to develop enough intelligence that they could hunt with tools? Would we see the rise of new dominant species as in Rise of the Planet of the Apes?

Well, shudder in your boots, people, because we are already there!

This week at Accumulating Glitches I talk about the discovery of how at least two species of crocodilians use tools to lure in prey. Check it out here.

And to learn more, check this out:

Dinets, V., Brueggen, J.C.. and Brueggen, J.D. Crocodilians use tools for hunting, Ethology Ecology & Evolution, (2013). DOI: 10.1080/03949370.2013.858276.

Let’s Talk Turkey: 8 Surprising Facts About Turkeys

A wild male turkey struts his stuff.
Photo by Lupin at Wikimedia Commons.

1. Turkeys are all-American. The modern domesticated turkey is descended from the wild turkey of North America, which is essentially a pheasant.

2. Domestic turkeys can’t fly or have sex. Domestic turkeys have been bred to have enormous breast muscles for our dinner tables. Their breast muscles have become so large that these top-heavy birds have lost the ability to fly and even to have sex! Domestic turkey eggs now have to be fertilized by artificial insemination. Wild turkeys with their functionally-sized breast muscles, however, can fly up to 55 mph for short distances and have sex just fine.

3. Male turkeys (called toms) are courtship-machines. Wild turkey males are substantially larger than females, and their 5,000 to 6,000 feathers have red, purple, green, copper, bronze, and gold iridescence. Like peacocks, male turkeys puff up their bodies and spread their elaborate feathers to attract mates and intimidate rivals. In comparison, female wild turkey feathers are duller shades of brown and grey to better hide from predators. And as if their flashy feathers weren’t enough, toms also have fleshy body appendages called snoods (the fleshy snotsicle that hangs over their beak) and wattles (the thing that looks like a scrotum under their chin). When the male is excited, the snood and wattle fill with blood and turn bright red. Sexy!

4. Turkeys are intelligent animals. They even have the ability to learn the precise details of a 1,000-acre area. And no, turkeys will not drown if they look up into the sky during a rainstorm.

5. Turkeys are social animals. They create lasting social bonds with each other and are very affectionate. Turkeys can produce over 20 different vocalizations, including the distinctive gobble (produced only by males), which can be heard up to a mile away! Individual turkeys have unique voices that they use to recognize each other.

6. Female turkeys (called hens) are good moms. Wild turkey babies (called poults) are precocial, which means that they hatch out of their eggs already covered in fluffy down and able to walk, run and feed themselves. They stick close to their mother for protection from predators, but unlike many other species of bird mothers, she doesn't have to feed them. Although wild turkeys roost in the trees at night to avoid predators, poults are unable to fly for their first few weeks of life. The mother stays with them at ground level to keep them safe and warm until they are strong enough to all roost in the trees with her.


A wild turkey mom and her poults. Photo by Kevin Cole at Wikimedia Commons.

7. Ben Franklin wanted the turkey to be America’s national bird. Benjamin Franklin famously argued that the wild turkey, not the bald eagle, should be America's national bird. In a letter to his daughter, he wrote, "For my own part, I wish the bald eagle had not been chosen as the representative of our country; he is a bird of bad moral character; he does not get his living honestly...like those among men who live by sharping and robbing...he is generally poor, and often very lousy. Besides, he is a rank coward; the little king-bird, not bigger than a sparrow, attacks him boldly and drives him out of the district...For in truth, the turkey is in comparison a much more respectable bird, and withal a true original native of America. Eagles have been found in all countries, but the turkey was peculiar to ours...".

8. Turkeys were once endangered. Although millions of wild turkeys used to live across the Americas, they were almost completely wiped out due to a combination of over-hunting and habitat destruction. Thanks to strong conservation efforts that included better hunting management, habitat protection, captive breeding, and reintroduction into the wild, wild turkey populations are now healthy and found in all of the lower 48 states.

Animal Biology in Science Fiction: The Color of Distance

Ani and two of her community’s elders are foraging when they stumble upon two seemingly lifeless aliens. They are able to restore one of the aliens to health and what follows is a thought-provoking story of first contact between alien worlds. This is Amy Thompson’s The Color of Distance, a science fiction novel written from perspectives that alternate between Juna (the human “alien” scientist stranded on a foreign planet) and Ani (the Tendu female that found her).

The Color of Distance is a rare science fiction story in that the science focuses on possibilities of ecology and physiology. The Tendu are a sentient species with many physical attributes similar to our own amphibians. They have a deep understanding of the ecology of their planet and they take responsibility for the sustainability of their ecosystems. We learn about their planet’s species and ecological relationships through the eyes and thoughts of Juna, a human scientist that was stranded on a mission to explore the planet. The parallels between the species and ecologies on this fictional planet and Earth are too similar for my critical science brain to believe, but they serve well to foster in us more of an appreciation for the wondrous complexities of our own planet.

The Tendu role as caretakers of their planet’s species is supported by their remarkable physiological abilities. The Tendu have fleshy spurs on their wrists, called allu, that they use to communicate and learn about the animals around them. By sinking their spurs into another animal, the Tendu can learn about that animal’s health, diet, emotional state, reproductive state, and many other attributes. Furthermore, through their allu they can manipulate other animals’ health, monitoring them, healing them, even physically altering them! This is a fun idea, but could this even be remotely possible?

In fact, many species on our own planet already have similar abilities! Many animals produce pheromones, chemical compounds that, when detected by another animal, communicate that animal’s health, diet, emotional state, reproductive state, and many other attributes. Many species (including many mammals and insects) use airborne pheromones, but fish and other aquatic animals can perceive chemicals in the water the same way. It is not much more of a conceptual leap to imagine an animal that can inject a spur into another animal’s body to “taste” chemicals that relate to that animal’s health and emotional state. If that spur were also able to release chemicals and compounds, then this could be a means to influence the receiving animal’s health and emotional state as well.

Thompson’s novel also takes us through the emotional journey of a woman trying to make a life for herself in a new land surrounded by people and customs she doesn’t understand. Her writing regularly left me lost in memories of my days in Peace Corps and will likely resonate with anyone who has spent a significant amount of time living abroad.

If you are looking to curl up with a blanket and a good book, this is a good one! It will get you thinking about physiology, ecology, culture and politics in a whole new way.

Have you read The Color of Distance? Can you recommend another science fiction book that focuses on physiology or behavior? If so, please comment below!

For more animal physiology and behavior in science fiction, go here.

The Importance of “Ancient Mating Habits of Whatever”



Photo of Wisconsin State Assembly
Speaker Robin Vos from WisPolitics.com
at Wikimedia Commons.

In the afterglow of the Republican national sweep in last Tuesday’s elections, Wisconsin State Assembly Speaker Robin Vos discussed his agenda for the next legislative session for the state of Wisconsin. Apparently, his agenda includes changes to the state’s support of the public University of Wisconsin System: “[We want] to make sure that people who are in the [University of Wisconsin] System are actually teaching, and they’re not using their time for purposes that don’t directly impact the lives ... of students,” Vos said. “Of course I want research, but I want to have research done in a way that focuses on growing our economy, not on, you know, ancient mating habits of whatever.”

For those of us that teach and do research, statements like these are hurtful and shockingly ignorant in many ways. But the biggest take-home message to me about this comment is how popular and dangerous this sentiment is across the nation because of the scientific community’s failure to communicate the relevance and importance of our work to the general public.

Scientific research takes two major forms: basic research and applied research. If we want “research done in a way that focuses on growing our economy”, we will generally turn to applied research: research that is geared towards solving a specific problem. However, in order to solve our specific problems, we need to have knowledge of how the systems work, what factors influence them and how those factors work. All of this general knowledge is obtained though basic research: research that is geared towards improving our knowledge or understanding without an immediate applied purpose. Applied research would not be possible without the foundation that basic research provides.

Everything we have depends on knowledge gained by past basic research. Many of our farming practices and cancer treatments would not be possible without the discovery of DNA. Medications for mental illnesses and seizures would not exist without continued research on neurotransmitters. The internet and satellite TV would not exist if it were not for support of basic research. Sometimes the potential future applications of basic research are obvious, but most of the time, they are not. Even basic research on the “ancient mating habits of whatever” could provide us with valuable insight on pest controls, agriculture and raising livestock, or even medical treatments. We don’t know exactly where basic research will take us, but we know it will take us forward.

Not only does the knowledge we gain from basic research move us forward, but the very act of conducting the research promotes economic prosperity. For example, the University of Wisconsin – Madison, the flagship university in the University of Wisconsin System, brings in approximately $1 billion every year in grants. This money provides jobs for the faculty researchers, their research staff and their graduate students. It provides additional jobs to people that maintain research facilities, care for research animals, and produce research equipment and supplies. The projects provide training and experience for post-docs, graduate students and undergraduates, who would not otherwise be able to compete for the jobs they aspire to. Simply getting good grades in college is not enough to get into graduate school, medical school or veterinary school. Schools and competitive jobs want applicants with experience. These basic research projects provide students with the opportunities to gain this experience under the supervision of an expert (who, by the way, is also a trained teacher). Supporting basic research is a win-win!

The dangerous lack of appreciation for the value of basic research is not just a Wisconsin problem; It is not just a United States problem; It is a global problem. The general public simply does not get enough information about the value of current research to understand why they should care. Let’s change this! Go to the Ancient Mating Habits of Whatever Facebook page and leave a post about basic research that has impacted you. Summarize your research in 140 characters or less and post it on Twitter with the hashtag #AncientMatingHabitsOfWhatever. Write your representative and tell him or her why basic research matters. Because we cannot move forward without it.

War and Peace



A group of Gelada baboons in Ethiopia.
Photo by A. Davey at Wikimedia Commons.

Syria and Iraq. Ukraine. The Gaza Strip. People are dying in large numbers at the hands of other humans, and for what? Land and resources? Is it really worth it? It is often said that humans are the only species so horrific as to kill its own species in war. But the fact is, we are not alone in what was previously thought to be a uniquely human trait. In many animal groups, individuals will band together in collective defense of territory and resources.

This week at Accumulating Glitches I talk about how group size influences the ability of primate groups to hold their territories. Check it out here.

And to learn more, check this out:

Willems, E.P. Hellriegel, B. and van Schaik, C.P. The collective action problem in primate territory economics, Proceedings of the Royal Society B, 280: 20130081 (2013). DOI: 10.1098/rspb.2013.0081.

Real Zombie-Making Parasites Among Us

The mummified cat and the rat in the crypt of Christ Church in Dublin.
Photo by Adrian Grycuk at Wikimedia Commons.

The Happening, M. Night Shyamalan’s worst panned movie of all time, is a science fiction thriller about people going into a mysterious trance and committing suicide as a result of other mind-hacking species. One of the leading criticisms raised against this movie is the ridiculousness of the premise. One species can’t cause another to willingly commit suicide! …Or can they?

Toxoplasma gondii (we’ll call it T. gondii) is a protozoan parasite that has developed just such mind-hacking abilities! As far as we can tell, T. gondii only reproduces in the digestive tract of cat species, where it lays fertile eggs that are pooped out into the environment. From there, T. gondii eggs can contaminate any number of things that are consumed by other animals, such as rodents, birds, or even humans. When cats eat prey animals that are infected with T. gondii, another generation of parasites is now positioned to reproduce and the cycle continues.

However, prey animals can be pretty good at avoiding cats, in part by avoiding the smell of cats. This is a problem for the reproductive plans of T. gondii. The tiny protozoan has responded to this problem with remarkable biological sophistication: They alter the behavior of their rodent hosts so that the infected rodents find the smell of cat urine so irresistible that they run straight towards their predators! Now, researchers have found that T. gondii-infected rats don’t only like the smell of cat urine, but they even prefer the smell of wild cat urine over the smell of urine of weaker domesticated cats.

A rat checks out odor-soaked papers
in a Y-shaped apparatus. Image from
Kaushik, et al. (2014) in
Integrative and Comparative Biology.

Maya Kaushik, Sarah Knowles and Joanne Webster at the School of Public Heath at the Imperial College of London compared the responses of rats that were either infected with T. gondii or not to urine produced by domestic cats or wild cats. To do this, they put infected or uninfected rats into a Y-shaped apparatus. For each trial, tissue paper soaked in domestic cat urine or wild cat (cheetah or puma) urine was placed in two of the three arms and nothing was placed in the third arm. The researchers then measured how much time the rats spent in each of the three arms and how much they moved.

As expected, the T. gondii-infected rats avoided the cat-urine-soaked arms less than the uninfected rats did. Furthermore, when presented with a choice between arms with wild cat urine versus domestic cat urine, the infected rats (but not the uninfected rats) preferred the smell of the predatory wild cats over the domestic cats! Infected rats also moved more slowly around the wild cat urine compared to domestic cat urine, as if just begging any wild cats that may be around to eat them. It appears that T. gondii have developed a mechanism to turn rats into mindless zombies that practically run into the mouths of the nearest, most vicious cat they can find.

These mind-hacked rat-zombies may not be the only victims of T. gondii. People (particularly those that change their kitties’ litter boxes) can also become infected with the parasite. Some estimates suggest that nearly one-third of all people are already infected! Furthermore, people that test positive for T. gondii infection find the smell of cat urine more attractive than people who test negative! Although we are not likely to run to be eaten by our house-bound kitties, we may be more likely to change the litter box (or get more cats and become a crazy cat lady). So it looks like many of us are mind-hacked zombies too!

Want to know more? Check this out:

Kaushik, M., Knowles, S., & Webster, J. (2014). What Makes a Feline Fatal in Toxoplasma gondii's Fatal Feline Attraction? Infected Rats Choose Wild Cats Integrative and Comparative Biology, 54 (2), 118-128 DOI: 10.1093/icb/icu060

Caught in My Web: Creepy Animals, Animal Disguises, Pet-Love After Death, and Ebola

For this Halloween edition of Caught in My Web, we check out what the web has to say about creepy animal stories.


1. The CDC addresses questions about whether pets can get ebola

2. Julie Hecht, the author of Dog Spies at Scientific American blogs explores the love between dogs and their owners from beyond the grave

3. BuzzFeed presents 8 surprisingly creepy animals.

4. Dr. Doolittle at ScienceBlogs talks about the eyeless Mexican cavefish

5. Sara Mynott at Saltwater Science, a blog at Nature’s Scitable blog network, explains flounder disguises (they’re not just for Halloween)

Is That Lizard Possessed!? (A Guest Post)

By Tawny Liebe

Image from Chuck Heston on Flickr.

A creature straight from the depths of hell… or at least as close as you can get on this planet. The Texas horned lizard or “horny toad” is found in the deserts of the southwest United States and has an unusual adaptation to deter predation exclusively from a few species of canines. When threatened by coyotes, foxes, and dogs, the horned lizard squirts blood from its eyes to hit targets up to three feet away! A total of six species of horned lizard have been proven to respond this way to canine attack, while none have responded this way to other predators, such as the grasshopper mouse or the roadrunner. So what is the deal? How do they do this and how does it work as predator defense?


Veins have one-way valves
to prevent backflow.
Drawing by Tawny Liebe.

Before we get to that, there are a few things you need to know. First of all, the circulatory system includes a network of arteries and veins. Arteries carry blood full of oxygen to body tissues while veins carry blood that lacks oxygen from the rest of the body back to the heart. This means that for the blood, in someone’s foot for instance, to get all the way back to the heart through the veins, the blood must work against gravity. When you (or this lizard or many other species) move, blood is propelled from one chamber in the vein to the next until it reaches the heart. The blood is prevented from flowing back into the previous chamber by one-way valves, causing the blood to pool.

In order to squirt blood from their eyes, horned lizards manipulate the network of veins in their head so that they build up pressure, like a volcano getting ready to blow. By constricting a pair of throat muscles unique to reptiles, they effectively close their jugular veins and increase the blood pressure in their head. This is thought to be enhanced by another pair of muscles between the jugular veins and the eyes that help increase the blood pressure in the head even further, causing the blood to move into the sinuses of the eyes. The pressure continues to build until the blood breaks through the wall of the eye socket into the eyelids where it is forced into the tear duct and erupts like a Mentos in a Coke bottle all over whatever is chomping at the poor little lizard.

As if these lizards couldn’t get any more amazing, recent studies have shown that it is actually a compound in their blood that canines don’t like. Scientists have also found that this chemical is in their circulating blood, not just the blood that is squirted from their eye, rejecting an earlier hypothesis that the chemical is picked up in the tear duct. To top off all of this awesomeness, the chemical may be acquired through its main food source- harvester ants, which are venomous. These ants aren’t actually a requirement of the horned lizard’s diet and yet they are specialized to eat them. The horned lizard’s blood plasma binds to the venom, which neutralizes its toxicity and the resulting compound may be what deters these canines.

Now that we know how horned lizards are capable of this type of defense and how they most likely make their blood so undesirable, what is it about this chemical that is so appalling to these predators? It appears that the target area of the blood is the mouth since the horned lizard only squirts the blood when the canine begins to bite down on its head. This suggests that it may be the taste of the blood that prevents the horned lizard from becoming that coyote’s tasty snack.

The horned lizard’s ability to squirt blood at canines to prevent their untimely death is truly amazing and complex and there is still much to learn about it. Their ability makes me wonder how many other cool anti-predator adaptations there are out there in the animal and even the plant kingdom! Below is a video that will allow you to appreciate the full effect of this awesome defense strategy, enjoy!

References:

Heath, J.E. 1966. Venous shunts in the cephalic sinuses of horned lizards. Physiological Zoology 39(1): 30-35.Middendorf, G.A. and Sherbrooke, W.C. 1992. Canid elicitation of blood-squirting in a horned lizard (Phrynosoma cornutum). Copeia 1992(2): 519-527.

Middendorf, G.A. and Sherbrooke, W.C. 1992. Canid elicitation of blood-squirting in a horned lizard (Phrynosoma cornutum). Copeia 1992(2): 519-527.

Middendorf, G.A. et. al. 2001. Comparison of blood squirted from the circumorbital sinus and systemic blood in a horned lizard, Phyrnosoma cornutum. The Southwestern Naturalist 46(3): 384-387.

Middendorf, G.A. and Sherbrooke, W.C. 2004. Responses of kit foxes (Vulpes macrotis) to antipredator blood-squirting and blood of Texas horned lizards (Phrynosoma cornutum). Copeia 2004(3): 652-658.

Sherbrooke, W.C. 1992. Chiricahua Mountains Research Symposium. Horny “toad” tales from the Chiricahua mountains as, told by a biologist. Southwest Parks and Monuments Association, Tuscon, AZ. 78-80.

The Biology of Nagging

A female pied flycatcher can't feed herself sufficiently
while she incubates her eggs and newly-hatched
chicks. Photo by Alejandro Cantarero.

I have been blessed with the fortune of not just having two healthy and happy babies, but being able to spend much of the spring and summer nurturing them and watching them develop and grow. But it has not been all roses: their smiles beam through the fog of my sleep deprivation and exhaustion. Their tears are met with my own. Our clothes are stained in a rainbow of bodily fluids. Now I am back at work trying to remember how my life used to be and how to meet my obligations to countless people, all while trying to keep up with the ever-changing needs of my daughters. Luckily, I am not alone. The girls have a rotating schedule with their grandparents one day, with their dad another, at daycare for a few days, and with me on weekends and evenings. But as the expectations on me grow heavier, I find myself pushing my husband harder to do more with the girls and around the house. Now it seems like every time I open my mouth, I am accused of “being a nag” and “for no reason” no less. The truth is, nagging has a deep biologically-based reason and may even be critical to species survival.

We are not the only species that nags, although in other species these vocalizations are often called “begging signals”. Begging signals are commonly heard in bird species in which the female does most or all of the egg and chick incubation. Because these females cannot sufficiently feed themselves while ensuring the survival of their brood, their male partners need to spend extra time foraging for the females in addition to foraging for the chicks and themselves. There is an inherent conflict between how mated males would prefer to spend their time (feeding themselves, maintaining their dominance status, and flirting with females) and how their female partners want them to spend their time (providing as much as possible for the family). The male response to this conflict is often to see how little he can get away with contributing while he sneaks off to spend his time as he wishes. The female response is to produce loud, juvenile vocalizations and gestures until he brings food to the nest. Is this really necessary though? Maybe she is just being manipulative to try to get him to do more than he really needs to.

Alejandro Cantarero, Jimena López-Arrabé, Antonio Palma, and Juan Moreno from the National Museum of Natural Sciences in Madrid, Spain and Alberto Redondo from the University of Córdoba in Spain set out to test whether the begging signals made by female pied flycatchers were an honest signal of need or were just obnoxious melodrama. They predicted that if the females’ begging calls were an honest reflection of how much help they needed, then begging calls would increase as energy needs increase.

The researchers studied 71 pied flycatcher nests in a forest in central Spain. Behaviors were observed by nest-mounted video cameras five days after the females finished laying their clutches of eggs. Two days later, each female was caught and measured, fitted with an identifying leg band, and had her wings clipped. About half of these females had their primary feathers clipped at the base to impair their ability to fly (these females are called the “handicapped” group). The other half had their primary feathers clipped at the tip so that their ability to fly would not be affected (these are the “control” females). When the females were released, they all returned to their nests. Their behaviors were measured again three days later.

Females in the handicapped group lost weight and begged significantly more after their wings were clipped, whereas the control females did not. This suggests that females are adjusting their begging rates to accurately reflect their needs. Furthermore, male partners of the handicapped females fed their partners more after the wing-clipping, whereas the male partners of the control females did not. This shows that the males are responding to either their partners’ increased begging or increased need or both. Revealingly, the amount that females begged was positively correlated with the amount that the males fed them, even when the researchers statistically controlled for whether their wings were clipped or not. This means that males were feeding females more because they begged more (and not simply because they needed more, which was also true).

This nagging female gets exactly what she needs.
Video by Alejandro Cantarero.

So, at least among pied flycatchers, females don’t “nag for no reason”, but because they genuinely need the help to keep their bodies and families healthy and safe. And males respond to the calls for help by increasing their contributions. But the graph that shows that males feed females more because they beg more also reveals that males would not help enough if females did not beg enough. Nagging is an adaptive strategy that females must engage in to meet the needs of the family.

Is someone nagging you too much? If we are like our pied flycatcher friends, than if you meet that person’s needs, the nagging should stop.

Want to know more? Check this out:

Cantarero, A., López-Arrabé, J., Palma, A., Redondo, A., & Moreno, J. (2014). Males respond to female begging signals of need: a handicapping experiment in the pied flycatcher, Ficedula hypoleuca Animal Behaviour, 94, 167-173 DOI: 10.1016/j.anbehav.2014.05.002

Animals That Have Twins

Here are a few animals that have twins:

Image by Michael Gabler at Wikimedia.

Common marmosets:















Image by David O at Wikimedia.

Anna’s hummingbirds:















Image by Legionarius at Wikimedia.

Evening bats:















Image by Jerome66 at Wikimedia.

Leopard geckos:
















They're so tiny! And yes, they held hands the moment they met.

Me!

You may have noticed my lack of posting as of late. It turns out, my twin daughters decided to make their appearance earlier than expected. Needless to say, I have had my hands quite full with this new and awesome role and I will be taking a bit of a maternity leave from The Scorpion and the Frog. But don’t worry; I will be back with more stories of the weird and wonderful world of animals next fall.

We Are Each A Community



Lactobacillus (the purple rod-shaped things)
is a common bacterial species in reproductive
tracts. Image by Janice Carr from the
CDC at Wikimedia Commons.

In our world of antibacterial soaps, we have learned that bacteria are evil, dirty, sickness-causing agents to be eliminated at all costs. Although some bacteria can cause sickness, bacteria in general are actually a critical component of animal bodies. A human body has ten times as many bacterial cells as human cells and a hundred times as many bacterial genes as human genes, and this pattern is likely true for most animals. We animals have bacterial communities living on our skin, fur, feathers, scales and exoskeletons. We have bacteria in our guts, respiratory systems and reproductive tracts. And bacteria live in glands that are specialized for grooming or scent communication. These bacteria play critical roles not just in how our bodies work, but also in how we behave.

This week at Accumulating Glitches I talk about how all animals (including ourselves) include a community of microbes, such as bacteria. Even more amazing is that many of these bacteria are critical for our health and behavior. Check it out here.

And to learn more, check this out:

Archie, E.A., & Theis, K.R. (2011). Animal behaviour meets microbial ecology Animal Behaviour, 82, 425-436 DOI: 10.1016/j.anbehav.2011.05.029

Caught in My Web: The Secret Lives of the Animals Around Us



Image by Luc Viatour at Wikimedia.

Most of us are surrounded by animals that we take for granted every day. We see them sleep and eat and clean themselves, and then sleep again. But our pets and yard-critters have secret and interesting lives. This week in Caught in My Web, we explore some of the lesser-known secrets of the animals around us.

1. Your dog poops in alignment with the Earth’s magnetic field.

2.  Your cat is just using you.

3. Some of the fish in your fish tank may change sex:

4. The birds at your birdfeeders have personalities, and some are liars.

5. Squirrels are the masters of… well, just about everything.

Freezing the Winter Away

The clutches of the Polar Vortex are finally releasing its grasp on us and we can be thankful for our home heating, our layers of warm clothing, and most of all, our bodies’ abilities to generate heat. But it is times like these that make me wonder about our friends that live outside year-round… especially those that don’t generate most of their own body heat. How do they survive these periods of intense cold? There are several species of North American frogs that have an unusual trick up their sleeve: They freeze nearly solid and still live to see the next spring.

This picture of a wood frog is by Ontley at Wikimedia Commons.

Frogs are ectothermic, meaning they take on the temperature of their surroundings rather than generate their own body heat. This introduces some intriguing questions about how these species even exist in northern climates that experience freezing temperatures every year. When various North American frog species (including wood frogs, spring peepers, western chorus frogs, and a few gray tree frog species) take on freezing winter temperatures, they actually allow their bodies to freeze nearly solid. For most species, this would be a deadly approach: a frozen circulatory system would halt the delivery of oxygen to cells, which require oxygen to generate the energy they need to do just about everything a cell does. Furthermore, jagged ice crystal edges could rupture the cells they are inside. Dead cells lead to dead organs, which in turn lead to dead animals. These freezing frogs have found the secrets to freezing without killing their cells.

The first secret of the freezing frogs is to spend the winter snuggled in the leaf litter below the snow. This environment insulates and protects the frogs from the deadly wind chills we have been facing for the last several days.

The second secret of the freezing frogs is a creative use of colligative properties. Colligative properties are properties of solutions that depend on the ratio of the number of liquid molecules to the number of molecules of stuff dissolved in that liquid. One of those properties is called freezing point depression: The temperature at which a liquid will freeze can be lowered by adding particles to it. (This is why salt is spread on roads in the winter). A critical component of the freezing frog strategy is for the liver to produce massive amounts of glucose in response to the start of freezing. This glucose is pumped throughout the body, which lowers the freezing point of all of the organs.

A third secret of the freezing frogs is the use of ice nucleating agents: proteins that actually encourage freezing. This may seem counterintuitive, but remember that ice crystals inside cells can cause them physical damage. By having a high concentration of ice nucleating agents in the fluid between the cells, this ensures that ice first forms in the spaces surrounding the cells. When ice forms, the ice crystals are made of only water molecules, which draws water out of the solution and leaves behind a higher concentration of other stuff (like glucose) in between the cells. The high concentration of glucose between the cells draws water out of the cells and into that space. This additional water also freezes. In the end, the cells are chock-full of particles, lowering their freezing temperature, and are surrounded by ice, which insulates the cells. Thus, this process of ice formation around the cells prevents ice from forming inside the cells.

A fourth secret of the freezing frogs is a metabolic shift. Most animal cells rely on oxygen to produce the energy they need to support their demands. But cells have ways of producing energy without oxygen too. These ways are not very efficient, but are useful when there is not enough oxygen available to meet demand (such as when a seal dives or a cheetah reaches burst speed). When freezing frogs start to freeze and oxygen delivery to the cells slows and eventually stops, their cells shift from an oxygen-reliant system of energy creation to an oxygen-independent system of energy creation. Additionally, freezing organs do less and don’t require as much energy anyway, so they can continue functioning at low levels for a long time if the freezing spell is prolonged.

When the environment warms up (as forecasters promise will happen), the body temperatures of these frogs raise and body fluids slowly become liquid again. The heart starts to beat again within hours of the start of thawing and oxygen can again be delivered around the body. The delivery of oxygen-carrying blood helps the rest of the organs return to their normal functions.

There are still many secrets of these freezing frogs left to uncover. Maybe you’ll be the one to do it… once we thaw out a bit.

Want to know more? Check these out:

1. Storey, K.B. (2004). Strategies for exploration of freeze responsive gene expression: advances in vertebrate freeze tolerance Cryobiology, 48, 134-145 DOI: 10.1016/j.cryobiol.2003.10.008

2. Layne, J.R., & Lee, R.E. (1995). Adaptations of frogs to survive freezing Climate Research, 5, 53-59 DOI: 10.3354/cr005053

Metabolism and Body Size Influence the Perception of Movement and Time

Zoetropes like this one have been used
for almost 2000 years. If you look in the
slits from the side, the image appears to
be animated. Image by Andrew Dunn
at Wikimedia Commons.

When we watch TV or a movie, we are essentially watching a series of still images presented in rapid succession… so rapid, in fact, that we perceive them to be a single moving image. The ability of movie-makers to convince us that still images are fluid in time is based on our physiology. Specifically, moving-pictures, as they were once called, rely on our critical flicker fusion frequency (CFF), the lowest speed at which we perceive a flashing light source to be a constant light. But we don't have our CFF so we can enjoy movies and TV; it came about from our need to identify and track moving objects.

The ability to identify and track moving objects is critically important for finding and catching prey, avoiding predators, and finding mates. It is these visual abilities that rely on an animal’s CFF. An animal with a low CFF will miss many visual details, like watching your TV with a fast-forward function that jumps ahead 15 seconds at a time. An animal with a high CFF will see all the details that happen in between with a fine-time-scale resolution. But if having a high CFF conveys such an advantage, why don’t all animals have a high CFF?

This week at Accumulating Glitches I talk about how an animal's size and metabolism can influence how it sees the world. Check it out here.

And to learn more, check this out:

Healy, K., McNally, L., Ruxton, G.D., Cooper, N., & Jackson, A.L. (2013). Metabolic rate and body size are linked with perception of temporal information Animal Behaviour, 86, 685-696 DOI: 10.1016/j.anbehav.2013.06.018