Tuesday, April 25, 2017

Can You Feel the Love Tonight? (A Guest Post)

A reposting of an article by Maggie Nannenhorn from March 14, 2016.

If you’re like me, you never truly realize how quiet winter is until all the sounds of spring come back in a chorus of celebration. Between the birds, crickets, and frogs, you can really hear the love in the air. So you can hear the love, but can you feel the love?

Wood frogs are known for their chorus of calls that sound like a duck laughing. Seriously, tell a duck a good knock-knock joke and that is what a male wood frog sounds like when trying to attract a mate. He makes the call by expanding his two vocal sacs, membranes of skin underneath the neck, forming a bubble-like appearance. When a female surfaces, drawn to the call, the male frog clasps onto her, causing her to lay her eggs. The male frog then externally fertilizes the eggs. This form of mating is termed amplexus. The use of the call in the reproduction ritual is well studied. However, it is possible the small ripple formed in the water from the expanding vocal sack is relaying information that influences the mating behavior of these frogs.


Male wood frog resting on the water surface. Image by Maggie Nannenhorn.
Male wood frog calling with vocal sac expanded.
Notice the ripple it creates in the water. Image by Maggie Nannenhorn.

In 2010, Gerlinde Höbel and Robb Kolodziej from the University of Wisconsin-Milwaukee conducted an experiment that explored the use of water surface waves in wood frog reproductive behavior. They hypothesized male wood frogs use ripples in the water to find female wood frogs to mate with, while female wood frogs use ripples in the water as indicators of harassing males.


Video of a wood frog calling by Maggie Nannenhorn.

Wood frogs have a very short mating period: only 1 to 3 days per year! This study occurred on April 1st - 2nd, which corresponded with the wood frogs’ natural mating period. The first component of the study was the observation of a pond containing more than 500 wood frogs in amplexus. Amplexus was determined by the presence of males clasping on to the backs of female frogs in the water. They learned males approach surface waves on the water and clasp onto the frog that caused the ripple. However, females move away from surface waves on the water and dive downward.

After preliminary observations, they developed an experiment to cause rippling of the water. The first experiment tested the effect of stimulation (dipping a wooden probe into the water) near male wood frogs. The males tested were randomly assigned to either a control group or an experimental group. The 34 males in the control group were simply observed, and the direction and pattern of movement was recorded. For the experimental group, a long wooden probe was dipped in and out of the water 25 cm away from a male frog for 10 seconds. The resulting ripple was meant to mimic a ripple caused by a female frog moving in the water. Based on the hypothesis, the male wood frogs should approach the ripple hoping to find a female to mate with. Of the 60 males in the experimental group, half were stimulated from the right and half were stimulated from the left. A circle diagram (depicted below) was used to map the direction the males moved.


video
Video of a wood frog approaching ripples by Gerlinde Höbel.


This figure shows: a) the control group and b) the experimental group.
A circle diagram representing the reproductively driven movement direction
of wood frogs (Lithobates sylvaticus) in a laboratory pool as a result of
stimulated surface waves on both the left and right sides.
Figure from: Höbel, G., & Kolodziej, R. C. (2013). Behaviour, 150(5), 471-483.

The females are difficult to observe in the field since they prefer to stay beneath the surface. So, the researchers set up a tank to test 4 breeding pairs of wood frogs. They tested the females both while in amplexus and while alone. They dipped wooden probes into the water to stimulate the females on both the left and the right side in turn. Their positions and directions were also recorded using a circle diagram.

So, what did they find? It turns out, their predictions were correct! The males would approach the ripple caused by the probing. This is likely because the ripple may indicate a competing male they want to drive away or a female they want to mate with. The females moved away from the ripples by either swimming away or diving underneath the water surface. This may reduce the amount of harassment they receive from males. If a female becomes the center of attention for too many males, she may drown from the weight of them all attempting to grab her. Besides, if a male is fit, he will likely be able to catch up to her and successfully mate with her despite her swimming away.

The mating calls and movement of the wood frogs affect the surface waves, and these waves are used to make sexual behavior choices. This spring, the chorus of love will still ring out through the reeds, and I encourage you to take a moment to stop and listen. When you’re stopped, take a moment to notice the waves of love bringing these wood frogs together. Hopefully this spring, we will all be feeling the love.



Reference:


Höbel, G., & Kolodziej, R. (2013). Wood frogs (Lithobates sylvaticus) use water surface waves in their reproductive behaviour Behaviour, 1-13 DOI: 10.1163/1568539X-00003062

Tuesday, April 18, 2017

What to Do If You Find Orphaned Wildlife

A reposting of an article from April 11, 2016.

A nest of baby cottontails waiting for sunset when their
mom will return. Image by Jhansonxi at Wikimedia.
Spring is finally in the air, and with Spring come babies! Finding baby animals in the wild is thrilling, but also concerning. Does this animal need your help? Where is its mom? What do you do?

Whenever possible, baby animals will do best when we leave them in the care of their mom. Even a well-meaning human is seen by a wild animal as a threat. Our interactions with them cause them extreme stress that can cause serious health problems and even death. Furthermore, if we take a baby animal home, it will not be able to learn its species-specific behaviors and skills and it can lose its natural and healthy fear of humans. It is also very hard to meet the specialized dietary needs of a wild animal in a captive setting. Taking a wild animal home can cause problems for us as well: many carry diseases that can be transmitted to our pets or even ourselves. And most wild animals are protected by state and federal laws that prohibit unlicensed citizens from possessing or raising them.

Luckily, most baby animals that seem alone actually have a mom that is not far away, either looking for food to feed herself and her babies or simply hiding from you. For example, rabbit mothers actively avoid their nests most of the time so as to not attract predators to the nest. Cottontail moms visit their babies only briefly at dawn and dusk for quick feedings. If you find a bunny nest, you can test to see if the mom is visiting by placing a few blades of grass or thin twigs in an X-shape over the babies. If you come back the next day and the pattern has been disturbed, then their mom is still caring for them and you should leave them be.

Many animal moms are prevented from taking care of their young when concerned people are hovering. Deer moms, for example, also actively avoid their babies (called fawns) so as to not attract predators to it. They generally return to nurse the fawns every few hours, but they won’t return to nurse if people or pets are around. If you find a fawn and it is not wandering and crying non-stop all day, then leave it alone so its mom will come back.

A red fox mom and baby. Photo by Nicke at Wikimedia.

Even if you find a baby all by itself in the open, the best course of action is often still to leave it alone. Many mammal moms, like squirrels, raccoons, mice, rats, foxes, and coyotes, will retrieve their young if they fall out of their nest or wander away from their den. Although it is a myth that most animal moms will abandon their babies if you get your smell on them, your odor can attract predators. It is best not to touch wildlife babies if you can avoid it.

Awww... as tempting as it is to pick up an adorable baby skunk, don't do it
unless you are a trained and licensed wildlife rehabilitator (like this woman is).
Image by AnimalPhotos at Wikimedia.

So when should you get involved? If an animal is in a dangerous location (like a busy street), then it may need to be moved. You can slowly, quietly and gently try to guide a mobile baby animal away from hazards and to a safer location. If the animal is not yet mobile, in most cases, you can use clean gloves to pick up the animal and move it to a safer location, placing it as close as possible to where you found it.

If you know that the mom is dead or has been relocated, then you are dealing with a truly orphaned baby animal. Likewise, if an animal has been attacked (or brought to you by your “helpful” cat), or is bleeding, injured, wet and emaciated, weak, infested with parasites, or has diarrhea, then it may need medical attention. In these cases, contact a licensed wildlife rehabilitator. Wildlife rehabilitators have been trained and have the necessary equipment to temporarily care for and treat injured, sick and orphaned wild animals so they can be released back into the wild. If you can’t find a wildlife rehabilitator, contact the Department of Natural Resources, a state wildlife agency, animal shelter, humane society, animal control agency, nature center, or veterinarian. Ideally, they will come to pick up the animal themselves. If they can’t, then they should give you detailed instructions for your situation on how to catch and transport the animal.

For more information, check here:

The Humane Society of the United States

The Wisconsin Department of Natural Resources

The Virginia Department of Game and Inland Fisheries

Tuesday, April 11, 2017

Risking Limb for Life? (A Guest Post)

By Matthew Whitley

Imagine you are walking alone in parking lot, when suddenly somebody grabs you by the arm and flashes a knife, demanding your money. Do you A) scream for help, B) try to wrestle the knife away, or C) remove your arm from your shoulder and make a break for it? Disarming your assailant may seem preferable to dis-arming yourself, but for a lizard option C is a likely response.

A lizard tail left behind. Image by Metatron at Wikimedia Commons.

You likely have heard before that many lizards can break off their tail when trying to make an escape. This ability is called caudal autotomy; autotomy meaning the ability to shed a limb, and caudal simply being a fancy word for tail. Of course, losing a limb is no simple procedure, and lizards possess many specialized features to make caudal autotomy possible.

There are two main kinds of caudal autotomy in lizards: intervertebral and intravertebral. Intervertebral refers to when the tail breaks between vertebrae, and is considered the simpler and more primitive form. Intravertebral, on the other hand, involves some more complex features. The word intravertebral refers to fracture planes found in the middle of each vertebra in the middle of the lizard’s tail. At these fracture planes, the bone can easily snap in half. This snapping of bone is performed by the lizard itself—when its tail is caught, muscles surrounding the bone just above where its tail is held squeeze tight until the bone breaks. After the bone breaks, the rest of the tail follows: the skin stretches and breaks, muscles detach, any remaining tissue divides, and—POP—the tail falls off!

After snapping your arm off to run from an attacker, you would probably just bleed out in your retreat, but lizards have that covered. In their tails, lizards have sphincters (rings of muscle) along their arteries—vessels that normally carry blood to the tail. When the tail is detached, these sphincters tighten to prevent blood from gushing out. Additionally, their veins, which normally bring blood back from the tail, have valves that prevent blood from flowing backwards, similar to the valves in your heart. And while the lizard makes its escape, the dislocated tail jerks and twitches, which distracts the lizard’s assailant. The tail owes its spastic actions to fast, glycolytic muscles, a variety of muscle that can act quickly and with a lot of force, but wears out quickly.

After our reptilian friend has made its daring escape, it has a new problem—it has no tail. A lizard without its tail is at a disadvantage, just as you would be without your arm. Lizards rely on their tails for several functions, including movement, nutrient storage, and social and sexual behaviors. Fortunately, lizards that exercise caudal autotomy can actually re-grow their tails, a process which itself is highly complex. In lieu of a lengthy explanation of another amazing phenomenon, I’ll share this tidbit: to regain lost nutrients and help recover, some lizards have been known to go back and eat their lost tail! So when you tear off your arm to escape a mugger, don’t forget to return to the scene of the crime to self-cannibalize…or maybe just buy some pepper spray beforehand.


Here you can see that the lizard is caught by the tail, pops it off and runs away, and the tail is left twitching.

Works Cited

Bateman, P., & Fleming, P. (2009). To cut a long tail short: a review of lizard caudal autotomy studies carried out over the last 20 years Journal of Zoology, 277 (1), 1-14 DOI: 10.1111/j.1469-7998.2008.00484.x

Clause, A., & Capaldi, E. (2006). Caudal autotomy and regeneration in lizards Journal of Experimental Zoology Part A: Comparative Experimental Biology, 305A (12), 965-973 DOI: 10.1002/jez.a.346

Gilbert, E., Payne, S., & Vickaryous, M. (2013). The Anatomy and Histology of Caudal Autotomy and Regeneration in Lizards Physiological and Biochemical Zoology, 86 (6), 631-644 DOI: 10.1086/673889

Tuesday, April 4, 2017

Researchers Finally Ask: Does Your Cat Even Like To Be Around You?

This cat has had enough and is running away
from home. Photo by Danielle Menuey.
While dogs happily and obliviously boast the reputation of being “man’s best friend”, cats have a reputation of being antisocial, independent, and downright grumpy. But do cats really deserve that? Scientists finally decided to find out.

Kristyn Vitale Shreve and Monique Udell from Oregon State University and Lindsay Mehrkam from Monmouth University asked 25 pet cats and 25 shelter cats their preferences.

How do you ask a cat what it prefers, you ask? You run a preference test, of course! A preference test is an experiment in which you place two or more things at equal distances from a subject and then test which of those things the subject spends the most time with.

Researchers suggest that these are some happy cats. Photo by Courtney Magnuson.

The researchers wanted to know if cats preferred: (1) food, (2) toys, (3) social interactions with humans, or (4) interesting odors. The trouble with that, however, is that there are many different foods, toys, interactions, and odors to choose from. So first, the researchers tested each cats' preferences within each category.

Will work for food. Photo by Charity Juang.
For food, the researchers put a soft chicken-flavored treat, actual chicken, and tuna into and around three puzzle boxes (so the cats would have easy access to taste some of each food, but couldn’t quickly gobble it up) and measured where the cats spent their time over a 3-minute period. Most of the cats liked the tuna most, next followed by the chicken, and they liked the soft treat the least.

For toys, the researchers made a movement toy by attaching a Dancer 101 Cat Dancer Interactive Cat Toy to a board and placing a GoCat Da Bird Feather Toy on the end with clear fishing line that was moved by an experimenter who was hidden outside the room. They then offered the movement toy, a still GoCat Da Bird Feather Toy on a board and a fuzzy shaker-mouse and they measured which toys the cats interacted with over a 3-minute period. Most of the cats liked the movement toy most, and they didn’t have much of a preference between the other two toys.

To test for cat preferences for types of human interactions, the cat’s owner (if it was a pet cat) or a researcher (if it was a shelter cat) spent one minute talking to the cat, another minute petting the cat (or holding their hand out to offer petting), and another minute playing with the cat with the feather toy (or holding out the toy). Researchers measured what proportion of each minute the cat spent interacting with the human. The cats interacted most with the humans during the play condition, next followed by petting, and least of all talking.

To see what odors cats preferred, the researchers put out cloths embedded with the scent of a gerbil (a potential prey), another cat, or catnip. The cats overwhelmingly preferred the catnip.

The preference test. Image from Vitale Shreve et al. 2017.

Once the researchers figured out what each cat preferred in each category, they set up a four-way grid with their favorite food, toy, social interaction, and odor and let them spend the next three minutes any way they liked.

Although there was a lot of variation among cats, 50% of the cats most preferred the social interaction with the human... even over food! Interestingly, the pet cats (who interacted with their owners) were no different in this regard than the shelter cats (who interacted with a researcher). But 37% of the cats most preferred food (maybe you have one of these cats). 11% preferred toys over all else. Only 1 cat (a pet named Hallie) preferred odor… the catnip fiend!

So although cats all have their own personalities, most of them really do like people. And they especially like to play with people. And, it turns out, they even do better at this than dogs (most of whom prefer food over people, when it really comes down to it). So go play with your kitty and give her some tuna… she’ll love you for it.

And, yes. This means that even cats can be trained with human interaction and food:


...But maybe not this one:

Some cats need more work than others. Photo by Jen Bray.


Want to know more? Check this out:

Vitale Shreve, K., Mehrkam, L., & Udell, M. (2017). Social interaction, food, scent or toys? A formal assessment of domestic pet and shelter cat ( Felis silvestris catus ) preferences Behavioural Processes DOI: 10.1016/j.beproc.2017.03.016

Tuesday, March 28, 2017

Bottlenose Dolphins: The Ultimate Sea Bully? (A Guest Post)

By Kayla Fuller

Imagine this situation: you’ve brought your favorite lunch to work. Everyone is jealous of your food, continuously eyeing it up. A few coworkers, who have brought in disappointing lunches in comparison, approach and demand that you hand it over. After you refuse, they beat you until your body lies lifeless and they take your lunch anyway.

Woah, woah, woah… that took a dramatic turn!

Photo of a harbour porpoise, taken by AVampireTear (Wikimedia Commons)

But for harbour porpoises in the northeastern Atlantic, this fight for food has become a reality, and bottlenose dolphins are the suspected culprit. In 1996, Harry M. Ross (SAC Veterinary Services, U.K.) and Ben Wilson (University of Aberdeen, U.K.) documented fractured rib cages, damaged internal organs and joint dislocations of deceased harbour porpoises in the northeastern Atlantic. Why would bottlenose dolphins be causing such damage? Who could ever associate such a cute and cuddly creature with a horrific crime like this?

Photo of a bottlenose dolphin, taken by NASA (Wikimedia Commons)

Researchers Jérôme Spitz, Yann Rousseau, and Vincent Ridoux with the Center for Research on Marine Mammals: Institute for Coastal and Environmental Research at the University of La Rochelle in France become the judge and jury in this trial. Jérôme, Yann, and Vincent obtained 29 harbour porpoises and 25 bottlenose dolphins that had been beached and died in the Bay of Biscay (between Spain, France, and England). At the time of the study, more harbour porpoises were being found dead in the bay than in previous years. They hypothesized that bottlenose dolphins and harbour porpoises may have had similar enough diets to cause competition and violence between the two species.

Photo of a harbour porpoise that received injuries thought to be from a
bottlenose dolphin before death (circled), from Ross and Wilson (1996)

The researchers’ goal was to analyze stomach contents to directly see what each mammal was eating at the time of their death. To do this, Jérôme, Yann, and Vincent removed the stomachs from the harbour porpoise bodies and weighed them with all contents included. After weighing stomach casings separately, they calculated total weight inside of the animals’ stomachs. Then, they washed stomach contents through a filter to separate out larger matter. Now, if you have a weak stomach, this probably wouldn’t be the job for you. Jérôme, Yann, and Vincent separated food items within the stomachs into identifiable categories. It could sometimes be difficult to recognize whole animals in a stomach due to breakdown, so methods like pairing dismantled eyes or counting fish bones was necessary to identify them! This same process was repeated for bottlenose dolphin carcasses. From there, the scientists compared specimens for prey presence, abundance, mass, and size to see if there was overlap between diets of the harbour porpoises and bottlenose dolphins.

So what did they find? More food mass, a greater number of species, and a more diverse size range of prey was found in the stomachs of bottlenose dolphins in comparison to harbour porpoises. Although bottlenose dolphins have a habitat that includes more deep-ocean areas while harbor porpoises inhabit coastal surroundings, certain prey species were eaten by both. Since bottlenose dolphins are bigger and hunt in larger groups, they would logically be more dominant in a face-off over a common prey item. Why are they fighting more over the same foods? This shift could be a result of humans harvesting species from the ocean that are diet items for bottlenose dolphins. It could also be a result of warming ocean temperatures that could be changing the dwelling places of available food for bottlenose dolphins. This would explain why more habour porpoises are being attacked by these marine tyrants moving into shallower waters.

Poor porpoises, all they want to do is eat their lunch in peace. Who knows, maybe in the next few million years, we’ll see highly evolved harbour porpoises covered in spikes to ward off the dolphins. That’ll teach those bullies!


References:

Ross, H., & Wilson, B. (1996). Violent Interactions between Bottlenose Dolphins and Harbour Porpoises Proceedings of the Royal Society B: Biological Sciences, 263 (1368), 283-286 DOI: 10.1098/rspb.1996.0043

Spitz, J., Rousseau, Y., & Ridoux, V. (2006). Diet overlap between harbour porpoise and bottlenose dolphin: An argument in favour of interference competition for food? Estuarine, Coastal and Shelf Science, 70 (1-2), 259-270 DOI: 10.1016/j.ecss.2006.04.020

Tuesday, March 21, 2017

The Weirdest Animals on Earth: 12 Amazing Facts About Platypuses

What IS that? A photo by Stefan Kraft at Wikimedia Commons.
1. Platypuses are so strange, that when British scientists first encountered one, they thought it was a joke: A Governor of New South Wales, Australia, sent a platypus pelt and sketch to British scientists in 1798. Even in their first published scientific description of the species, biologists thought that this duck-beaked, beaver-bodied, web-footed specimen may be some Frankenstein-like creation stitched together as a hoax. But this is only the beginning of their oddities…

2. Platypuses are egg-laying mammals. Mammals are animals that have a backbone, are warm-blooded, and females produce milk for their young. Most females that nurse their young also carry their developing babies in their bodies and give birth to live young… But platypuses don’t play by those rules. Platypuses are monotremes, egg-laying mammals that include the platypus and four species of echidna. Most female mammals have two functional ovaries, but female platypuses, like most female birds, only have a functional left ovary. Once a year, a female platypus may produce a clutch of two or three small, leathery eggs (similar to reptile eggs), that develop in her uterus for 28 days. Because female platypuses don’t even have a vagina, when the eggs are ready, she lays them through her cloaca, an opening that serves for reproduction, peeing and pooping. (In fact, monotreme comes from the Greek for “one hole”). She then curls around them and incubates them for another 10 days until they hatch.



3. Platypuses sweat milk! Not only do female platypuses not have vaginas, they don’t have nipples either! Instead, lactating mothers ooze milk from pores in their skin, which pools in grooves on their bellies so the babies can lap it up. …And they’re not even embarrassed about it!

4. Adult platypuses are toothless. Baby platypuses (that is the actual technical term for them, by the way… not “puggles”, which would be way more fun) are born with teeth but they lose them around the time that they leave the breeding burrow. In their place are rigid-edged keratinized pads that they use as grinding plates. When they catch their prey (worms, bugs, shrimp, and even crayfish), they store it in their cheek pouches and carry it to the surface, where they use gravel to crush it in their toothless maw.

5. The platypus “duck bill” is a sensory organ used to detect electric fields. Muscles and neurons use electrical impulses to function, and these impulses can be detected by electroreceptors. Although common in shark and ray species, electroreception is rare in mammals, only having been discovered in monotremes and the Guiana dolphin. Platypuses have rows of around 40,000 electroreceptors on their highly sensitive bill, which they wave back and forth in the water, much like a hammerhead shark, to determine the location of their prey. It’s a good thing this sense is so sensitive, since they close their eyes, nose and ears every time they dive.



6. Platypuses don’t use their tails like beavers do. Whereas beavers use their large, flat, leathery tails for swimming and slapping the water to send signals, platypuses don’t use their tails for any of that. Platypuses have large, flat tails for storing fat in case of a food shortage. Unlike beaver tails, platypus tails are covered in fur, which the mothers use to snuggle with their incubating eggs.

A platypus ankle spur. Photo by E.Lonnon at Wikimedia Commons.
7. Male platypuses have venomous ankle spurs. Their venom is strong enough to kill small animals and to create excruciating pain in humans. Since only males have it and they produce more venom during the breeding season, we think its main function may be to compete for mates and breeding territories.

8. Platypuses are knuckle-walkers with a reptilian gait. Although they are well-built for swimming with their webbed feet and legs on the sides of their bodies, these traits make it quite awkward to get around on dry land. To walk, they pull in their webbing and walk on their knuckles, exposing their claws. Like reptiles and salamanders, platypuses flex their spines from side-to-side, supported by their sprawling legs.



9. Platypuses have unusually low body temperatures. As unusual as they are, platypuses are still mammals, which are defined, in part, by their ability to generate most of their own body heat with their metabolism. Platypuses do this as well, but whereas most mammals maintain body temperatures between 37-40 degrees C (99-104 degrees F), platypuses are happy with a body temperature of 32 degrees C (90 degrees F). This lower metabolism reduces the amount of calories they need to eat.

10. They have no stomach. Stomachs are specialized protein-digesting chambers of digestive tracts that contain protein-digesting enzymes and acids to activate them. Not all animals have them, but most carnivores do. The most common exceptions to this rule are fish… and platypuses. Why? We don’t know for sure, but many of these animals consume diets high in calcium carbonate, which is a natural antacid. If their own diet would constantly neutralize their stomach acid, then the stomach really isn’t going to do them any good anyway.

11. They have 10 sex chromosomes! Most mammals have two sex chromosomes, one from each parent. An individual that has two X chromosomes is usually female and an individual that has one X and one Y chromosome is usually male. Thus, female mammals pass along an X chromosome to each offspring and males can pass along an X or a Y. But platypuses are not content to be normal in any way…They have 10 sex chromosomes: 5 from mom and 5 from dad. All 5 chromosomes from mom are Xs, whereas a male sperm either contains 5 Xs or 5 Ys. Birds also have two sex chromosomes, but in birds, individuals with two of the same type are usually male and individuals with different chromosomes are usually female. Their system is called ZW, where the mammalian system is XY. The platypus X chromosome is more similar than the X chromosome of other mammals to the bird Z chromosome.

12. The platypus genome is as much of a hodgepodge as its body. Only 80% of the platypus’ genes are like other mammals. Some of their genes have only previously been found in birds, reptiles, fish, or amphibians.

To learn about more weird animals, go here.

References:

Scheich, H., Langner, G., Tidemann, C., Coles, R., & Guppy, A. (1986). Electroreception and electrolocation in platypus Nature, 319 (6052), 401-402 DOI: 10.1038/319401a0

Warren, W., Hillier, L., Marshall Graves, J., Birney, E., Ponting, C., Grützner, F., Belov, K., Miller, W., Clarke, L., Chinwalla, A., Yang, S., Heger, A., Locke, D., Miethke, P., Waters, P., Veyrunes, F., Fulton, L., Fulton, B., Graves, T., Wallis, J., Puente, X., López-Otín, C., Ordóñez, G., Eichler, E., Chen, L., Cheng, Z., Deakin, J., Alsop, A., Thompson, K., Kirby, P., Papenfuss, A., Wakefield, M., Olender, T., Lancet, D., Huttley, G., Smit, A., Pask, A., Temple-Smith, P., Batzer, M., Walker, J., Konkel, M., Harris, R., Whittington, C., Wong, E., Gemmell, N., Buschiazzo, E., Vargas Jentzsch, I., Merkel, A., Schmitz, J., Zemann, A., Churakov, G., Ole Kriegs, J., Brosius, J., Murchison, E., Sachidanandam, R., Smith, C., Hannon, G., Tsend-Ayush, E., McMillan, D., Attenborough, R., Rens, W., Ferguson-Smith, M., Lefèvre, C., Sharp, J., Nicholas, K., Ray, D., Kube, M., Reinhardt, R., Pringle, T., Taylor, J., Jones, R., Nixon, B., Dacheux, J., Niwa, H., Sekita, Y., Huang, X., Stark, A., Kheradpour, P., Kellis, M., Flicek, P., Chen, Y., Webber, C., Hardison, R., Nelson, J., Hallsworth-Pepin, K., Delehaunty, K., Markovic, C., Minx, P., Feng, Y., Kremitzki, C., Mitreva, M., Glasscock, J., Wylie, T., Wohldmann, P., Thiru, P., Nhan, M., Pohl, C., Smith, S., Hou, S., Renfree, M., Mardis, E., & Wilson, R. (2008). Genome analysis of the platypus reveals unique signatures of evolution Nature, 453 (7192), 175-183 DOI: 10.1038/nature06936

Tuesday, March 14, 2017

The Physiology of Your “Sense of Self”

Quick! Name all of your senses!

Now, close your eyes and wave your arms over your head. Which of those senses are helping you know where your arms are in space?

The answer is the often-forgotten sense of proprioception. Proprioception (derived from the Latin for “sense of self”) is an animal’s sense of its body’s position in space. We have several different specialized receptor cells that all detect a change in body position in different ways.

Grays muscle picture by Mikael Haggstrom
at Wikimedia Commons.
If you raise your arms over your head as if you are going to grab a pull-up bar, then some muscles in your back (like your trapezius muscles), shoulders (like your deltoids and rotator cuff muscles), and arms (like your triceps) will contract. Muscles are all connected with tendons to the bones they pull on. When a muscle contracts, its tendons are stretched. Specialized proprioceptor cells called Golgi tendon organs merge with tendons and detect when their corresponding muscle is being stretched. Together, they inform the brain about muscle tension in muscles all across the body.

Grays muscle picture by Mikael Haggstrom
at Wikimedia Commons.

However, while some muscles will contract during your movement, other muscles in your chest (like your pecs) and arms (like your biceps) will stretch. Each muscle contains muscle spindles, another kind of specialized proprioceptor cell. Muscle spindles are wrapped around individual muscle fibers within the muscles. They send signals to the brain to let it know when the muscle is stretched and by how much.

Joint receptors are specialized proprioceptor cells located between bones in the capsular tissue of joints. When the angle of a joint changes, the bones and tissues put pressure on the joint receptor, causing it to send a signal to the brain. Your brain collects information from all of your Golgi tendon organs, muscle spindles and joint receptors to know the angle of each joint and the tension and length of each muscle in your body, and thus, your body’s position in space.

gif by Extremistpullup at Wikimedia Commons.
Some animals, and some individuals, are better at this than others. This guy should be pretty proud of his proprioceptive abilities (and strength). But then again, let’s see him try this:



Tuesday, March 7, 2017

Caught in My Web: Perplexing Animal Behaviors

Image by Luc Viatour at Wikimedia Commons.
Sometimes animals behave in such an odd manner, that even the animal behaviorists aren't sure what the heck they are doing or why. So for this edition of Caught in My Web, we just wonder.

1. Last month, a dog was hit and killed by a car. His fellow doggy-companion then used his nose to bury him. Was this a funeral? Is this just canine burying behavior? We don't know, but it's been seen before. This video is from 2013:



And here is another from 2015:


2. Have you seen this video of turkeys circling a dead cat?

3. An African elephant approaches a white rhino with a branch across his nose. Was he trying to play or was he bring aggressive? Either way, the rhino wasn't taking any chances. Watch the exchange here.

4. A South American Magellanic penguin swims 5,000 miles every year to be reunited with the man who saved his life. Read the heartwarming story here.

5. An octopus inflates itself like a giant balloon across the ocean floor and scientists can't agree if it is hunting or showing defense behavior. What do you think?

Tuesday, February 28, 2017

Astonishing Animal Sleeping Patterns (A Guest Post)

By Eugene Gabriel

Image from Pexels.
Sleeping patterns across the animal kingdom are just as amazingly interesting and diverse as the animal kingdom itself. While some sleep with half their brain alert, some can go weeks without sleeping. While some take power naps lasting only a minute, some can snooze for 3 years. Keep on reading for some astonishing yet adorable animal sleeping patterns.


Giraffes


The tallest mammal in the world has one of the shortest sleep requirements. Did you know giraffes can go weeks without sleep? When they do sleep it's for short bursts of only 5 minutes with a total of no more than 2 hours in a day. Giraffes sleep in an upright standing position with their neck curled up to rest their head on their hind. They curl up to sleep in a similar fashion while sitting too which is quite an adorable sight but a rare one too. That's because in the wild they always have to be on their toes and in case of a wild cat pouncing on the herd, it really is a task to get those long legs back on the ground and going.


Horses


Like giraffes, horses are also standing sleepers. They are able to lock their legs in a straight standing position in such a way that it doesn’t require much muscle effort. So in this way they can stay alert even in rest mode. But to experience REM (rapid eye movement) sleep they must sit down. This means that like us humans horses also dream.


Meerkats


Image from Ltshears at Wikimedia Commons.
Meerkats are pack animals and they sleep in the same way too. They do this by getting on top of each other and making a heap, like puppies. In this way they are able to stay warm in the cold desert night. The pack leader sleeps at the bottom getting the best sleep and staying protected from predators.


Desert snail


The longest nap award goes to the desert snail which has been known to snooze for three years.


Dolphins


Dolphins literally sleep with one eye open! When sleeping dolphins will only shut half of their brain and close the opposite eye (when the right part of the brain sleeps the left eye is closed). After two hours or so, the sides switch, so both eyes and brain hemispheres get their due rest. Sounds weird right? But unlike humans who breathe automatically, dolphins breathe consciously. This means that they cannot go into deep sleep because they could suffocate from lack of air and drown. So while one half of the brain rests, the other half remains active and controls breathing functions. This also helps to monitor dangers in the environment.


Ants


We see ants working day and night and it seems that they hardly ever sleep but research shows that ants takes about 253 power naps lasting 1.1 minutes, on a daily basis.


Otters


Otters sleep in the cutest way by laying their backs on the surface of water and holding hands with each other. They do this to prevent themselves from floating away. They sleep for around 6 hours a day.


Lions


Image from Charlesjsharp at Wikimedia Commons.
Sitting at the top of the food chain, lions and other big cats have no fear of predators. So once they have feasted on their prey they can take a long peaceful nap. Lions are known to sleep for 13 hours a day.


Swainson’s Thrushes


Migratory birds like Swainson’s Thrushes have to fly incredibly long distances. So they catch up on their sleep whilst flying and take hundreds of power naps lasting only a few seconds at a time. They have also adopted another form of sleep, like dolphins in which they rest one eye and one half of their brains while the other half of eye and brain remains alert.

Animals never cease to amaze us and the variety of ways in which animals sleep is just astonishing. But unlike us humans who can forget about everything as soon as we hit the hay, animals have to constantly monitor their surroundings for survival in the wild.


References:
Livescience
Huffington Post

Tuesday, February 21, 2017

Who Can Swim Further: A Race to the Depths and Back (A Guest Post)

By Jefferson Le

The blue whale (Balaenoptera musculus) is the largest mammal on the planet. Image by
NMFS Northeast Fisheries Science Center (NOAA) available at Wikimedia Commons.
Helloooooo! My name is Bailey and I am a 25 meter long blue whale, the largest living mammal on Earth! My friend Finley, a 21 meter long fin whale comes in second for largest in size. We had an interesting adventure recently where we were followed by humans. While Finley and I were foraging for food, I overheard the humans talking about investigating our diving behavior when we hunt and not hunt. With that, I will tell you what these foreigners did to investigate our behavior and also what happens when we dive.

A chart of whales of different sizes. Image by Smithsonian Institute.
To record our dives, the humans travelled to Mexican waters to attach recorders onto our mid-backs using a crossbow. Now, it didn’t hurt much due to my thick blubber. These devices recorded depth of how far we dived, time of dives, and our location. These recorders eventually came off between 5 to 13 hours later. Finley and I were not the only test subjects. Other members of our species were also tagged. After all the data on the devices were collected, the humans finally left our waters and did statistical analyses on our diving behavior.

The fin whale (Balaenoptera physalus) rarely exposes its fluke when it prepares to dive
to the abyss. Image by Aqqa Rosing-Asvid at Wikimedia Commons.
Now, before we talk about what the humans found, I want to share with you the whale secret to a great dive. In case that you ever find yourself in the ocean or your local pool, you can try it! The nose for Finley and I are called blowholes, which are found on top of our heads. This tract is separated from our digestive tract so we do not have to worry about having food go down our blowhole. When I am about to dive, instead of gulping in lots of oxygen, I exhale out as much as I can. This causes my lungs to collapse and flexible walls in my chest allow even more compression. Also, tiny structures in my lungs called alveoli collapse which halts any gas exchange. All of the decrease in lung space decreases buoyancy so I can descend down to the depths.

As I descend, my heart rate lessens to reduce energy used during the dive. The oxygen that I had obtained before the dive is stored in my blood and muscle tissue. Since the deep depths are really cold, blood flow is temporarily halted at the thinner areas of my body, like flippers, and some organs to keep the main body going. When I ascend back up, I gradually increase space in my lungs and my alveoli regain full function to allow gas exchange. If you were to ascend too quickly, you could get shallow water blackout or even worse, the “bends” (where nitrogen bubbles in your blood) and I heard it is painful. After ascending is complete, I can release my blowhole open and take in fresh oxygen again.

I was secretly told what the results to the humans’ experiments were. They found out that fin and blue whales dove deeper when hunting on shallow dives when not hunting. It makes sense! Why spend so much energy diving when not hunting? Also, they noted that our lunge feeding frequency was different. Lunge feeding is where we propel ourselves towards our prey with our mouth open and grab as much food as we can into our mouth. Blue whales lunged about 2.5 times more than fin whales! That’s a point for the blue! However, the record dive depth came from a fin whale. Hmm… I wonder if Finley broke that record.

Did you find my secret and what the humans found interesting? I surely did. I never thought about how I dive and how I behave as it is practically in my blood! Well, the next time you are at a deep pool, try those secrets I spilled to you. It might be fun! Then again, you might be thinking, how does a whale communicate with a human and understand scientific data? That is a secret you may never know…


Literature Cited:

Croll DA, Acevedo-Gutiérrez A, Tershy BR, & Urbán-Ramírez J (2001). The diving behavior of blue and fin whales: is dive duration shorter than expected based on oxygen stores? Comparative biochemistry and physiology. Part A, Molecular & integrative physiology, 129 (4), 797-809 PMID: 11440866

Hill, R. W., G. A., Wyse, M. Anderson. (2008). Animal Physiology. 2:641-660

Tuesday, February 14, 2017

The Complexities of “The Love Hormone”

New York street art. Photo in
Wikimedia Commons posted by Pedroalmovar.
Oxytocin, commonly known as “the love hormone”, is a small chemical that is produced in the brain of mammals, but can both act as a neurotransmitter and enter the blood stream and act as a hormone. It has long been heralded for its role in both maternal and romantic love, but more recent research is showing us just how complicated the physiology of love can be.

Oxytocin is released in mammalian mothers after birth. It promotes nursing and bonding between a mother and her young. As children grow, oxytocin is involved in how both mothers and fathers “baby-talk” and mirror their children. It is involved in pro-social behaviors in both young and adults: trust, generosity, cooperation, hugging, and empathy. And of course, oxytocin promotes positive communication and pair bonding in romantic couples. Countless studies have found these relationships between affiliation and oxytocin in many mammalian species, giving oxytocin its commonly used nickname “the love hormone”.

But more recent studies show that it’s not so simple.

In a number of recent studies, people have been given oxytocin nasal sprays and tested for various behavioral effects in different contexts… and the context really seems to matter. Oxytocin increases trust, generosity, cooperation, and empathy towards people we already know and like. But it decreases trust, generosity, cooperation, and empathy towards strangers. When we play games with strangers, oxytocin makes us more jealous when we lose and it makes us gloat more when we win. It also seems to enhance many attributes relating to ethnocentrism: It increases our ability to read facially-expressed emotions in people of our own race while making it harder to read facial expressions of people of a different race. When forced to choose between being nice to a stranger of our own race versus a stranger of another race, oxytocin makes us more likely to choose the person of our own race. In studies of both people and rodents, oxytocin decreases aggression towards our families and friends, but increases aggression towards strangers.

Oxytocin is not the universal love hormone we once understood it to be. It helps us direct our positive support towards our “in-groups” (our family and friends) and defend them from our “out-groups” (individuals we don’t know). It is a delicate balance: Too little of it can cause social impairment and make it difficult to connect with loved-ones; Too much of it can increase our anxiety towards strangers and racist tendencies. And to make things more complicated, each of us has a slightly different oxytocin system: sex, gender, social history, history of childhood trauma or neglect, psychiatric illnesses and genetic variations all have profound effects on the oxytocin system.

There is much we don’t know about the role of oxytocin and love. But they are a good fit, because both, it seems, are complicated.


Want to know more? Check these out:

Shamay-Tsoory SG, & Abu-Akel A (2016). The Social Salience Hypothesis of Oxytocin. Biological psychiatry, 79 (3), 194-202 PMID: 26321019

Zik JB, & Roberts DL (2015). The many faces of oxytocin: implications for psychiatry. Psychiatry research, 226 (1), 31-7 PMID: 25619431

Tuesday, February 7, 2017

How to Get into Veterinary School: The General Application Process

By Mary Harman

Is this where you want to be?
Photo by Elizabeth Martens.
The field of veterinary medicine is not only a profession that has been around for centuries, but is one that remains respectable and ever-expanding in the modern world. However, the field also remains a highly competitive one; according to the AAVMC (Association of American Veterinary Medical Colleges) there are 30 accredited veterinary colleges in the United States and each one only accepts, on average, 80-100 students a year. There are also 25 accredited veterinary colleges outside of the United States if studying abroad is more your style. A full list of accredited vet schools is available on the AAVMC website. So, while a passion for animals and their care is indeed important to becoming a veterinarian, more aspects must be taken into account when looking into the field of veterinary medicine: the cost, work, applications, grades, and most importantly: reward. But if you’ve decided that you are willing to jump into this world, then there are a few things you need to do before you start applying.

The application process for vet school tends to be quite lengthy, and it is highly recommended that you begin this process long before the application deadlines. Most of the accredited veterinary colleges in the US and many outside the US require the completion of a Veterinary Medical College Application Service (VMCAS) application. This application is essentially a single, secure, online copy of your vet school application that can be distributed by AAVMC to your desired schools electronically. The goal is to allow you to keep all of your shadowing hours, courses taken, GPA, and personal information in one convenient location. Note that there is a fee associated with submitting your VMCAS application that is based on the number of schools you are applying to, and a strict VMCAS deadline each year (to learn more about the VMCAS: check out “VMCAS- In Depth!”-coming soon, or VMCAS FAQs).

One important thing to note is that you do not, and I emphasize the not, need a bachelor’s or even an associate’s degree to apply to veterinary school. However, there is often a list of college classes and credits that you need to complete before applying (see The Academic Phase, below). Since most veterinary schools require similar courses, they will also follow a similar application process that is designed to pick out the best applicants. These processes often involve at least three steps, or phases. Each one is important, but some colleges may lean more heavily on one of the three when making the final decision.



The Academic Phase


The Academic Phase is where the admissions staff look at your grades and all of the academic aspects of your application. They glance over the courses that you have taken to see if you have fulfilled the set of requirements they believe are important. In general, most vet schools require a minimum amount of English, math, and social science credits. They will also require general biology classes, including genetics, some form of animal biology or zoology, and several upper level biology classes (often including physiology, microbiology, and anatomy). Every school is different on the exact specifications of the classes they expect, so you should research the requirements for any school you are considering applying to. A List of course requirements for each AAVMC accredited school can be found here.

Getting into vet school requires lots of this.
Photo by Mary Harman.
The admissions staff also look at your cumulative GPA, and some schools will look at your science GPA and/or your GPA of your last 45 credits. Most veterinary colleges list the minimum GPA needed to apply as somewhere between 2.75 and 3.0; however, most have a competitive GPA between 3.5 and 3.75. That means that during senior and junior year, you need to work just as hard to maintain your grades as any other semester: No senioritis allowed (okay maybe a little, but that depends on the classes you are taking).


For studying advice, read this.

This is also where they look at your GRE composite score, but some schools will look at the individual sections as well. The GRE, or Graduate Record Examinations, is a standardized test that consists of three sections: Verbal Reasoning, Quantitative Reasoning, and Analytical Writing. The GRE is completely computerized and lasts about 4 hours. This test must be taken and sent to your preferred schools before you send in your applications. For many veterinary colleges, a competitive GRE composite score for admittance is above 300 out of a possible 346.



The Personal Phase


It is important to get a range of animal experience.
Photo by Mary Harman.
The Personal Phase is the section on the application where you will talk about yourself. This section often starts with a personal statement. The personal statement is basically where you explain why you want to go to vet school and why you think you have what it takes. This section is also where you include all the animal experience and veterinary experience you have obtained going all the way back through high school. There is no minimum number of hours of experience that is required for vet school, however most applicants have at least 500 hours.

Some schools will differentiate between animal experience and vet experience, so keep that in mind when you are applying to schools, and when you are obtaining your shadowing hours, internship and work hours, and volunteer opportunities. All of these areas count towards your experience one way or another. It is extremely important to try and work with a variety of animals, clinics, and vets to help your application stand out among the mountainous stacks of applications that the veterinary colleges receive.

Many veterinary colleges require that you shadow more than one vet in a certain discipline, and in other areas of the practice to make your application well-rounded; however, the general rule is that most of your shadowing hours should be with vets in the certain discipline you want to work in once you graduate. For example, if you wish to work in a small animal clinic after you graduate the majority of your hours shadowing should be with small animal vets. Keep in mind though, when you are in vet school you will be learning about and working with several different species.

Another benefit of shadowing is forming a professional relationship with the doctors, which can come in handy for obtaining your letters of recommendation, and also once you graduate and are searching for a job. The letters of recommendation are required for vet school, and most schools require three letters. The letters do not all have to be from veterinarians, but most prefer at least one letter of recommendation from a veterinarian. This generally nerve-racking task can be made slightly easier if you have already established a relationship with a vet that you have been shadowing or working with.



The Interview Phase


The interview phase is the most exciting, and probably the most nerve-racking, phase of the whole process. It often signals that out of all the applications received (some of the larger schools receive over 800 applications a year) the administrative members were impressed by yours, and would like to interview you personally. This is generally a good sign. For most schools a good interview can have a huge influence on your acceptance; good interview skills and be a major advantage in such a competitive process. If your undergraduate college offers a seminar on interview etiquette, it may be in your best interest to attend at least one. This way you can be prepared for your interview, and hopefully feel a little less nervous.

Another piece of advice, as you consider veterinary medicine, is that many prospective veterinary students find it helpful to go and visit their schools of interest. Don’t be shy about reaching out to the admissions directors about taking a tour of the facilities. Many veterinary colleges offer days that are strictly designed for interested students to go and get a tour of the school. These tour days usually are led by a student currently in the program, at least for a portion of the day, and most of them are super open about answering any questions you may have (after all, they were once in your shoes too).

The processes and preparations needed to get accepted to vet school requires an enormous amount of dedication and commitment to education (but it is possible I promise); you must be willing and eager to pursue shadowing hours, internships, and jobs, on your own. However, if you are willing to put in the work and the time required the reward is great. Some day you will get to go home from work with the knowledge that you are saving numerous animals’ lives, easing their pain and illness, and creating a sense of peace for the owners who call them family.


References:

AAVMC website, FAQ’s

VMCAS FAQ’s and Instructions

VMCAS Home


For more advice on careers with animals, check this out.