Caught in My Web: What the WHAT?

Image by Luc Viatour at Wikimedia Commons.

For this edition of Caught in My Web, we just wonder.

1. Scientists confirm that zebra stripes are not for camouflage… or even to help recognize one another. Anyone got another idea?

2. Want to surf in the ocean without fear of sharks? A shark deterrent wet suit is explained in this TED talk.

3. The woolly mammoth may be brought back from extinction in just a few years!

4. Gorilla treetop slumber antics were caught on tape for the first time.

5. Some towns wake up covered in giant spider webs. Here's why.

Catch Him If You Can (A Guest Post)

By Caitlin Lockard

When playing Frisbee with your dog, do you ever wonder how they have the ability to catch it so effortlessly? The art of being able to figure out where something like a Frisbee is headed requires some crazy math skills. Ostracods are one kind of animal that puts their wicked math skills to the test while finding a mate.

The image above of a female ostracod was provided by Trevor Rivers.

You’ve never heard of an ostracod you say? Ostracods are small crustaceans, which basically means they have lots of legs and are covered by a hard shell. Male ostracods can be seen roaming throughout the ocean trying to enchant females with light displays. Typically, just after sunset, males begin their light displays, which consist of two phases. The first phase is the bright phase, which is short. The goal here is to signal to the female that “I’m here, single (except all my buddies that I brought with me of course) and ready to mingle”. The second phase is where males spiral up in a helix while pulsing repeatedly. This phase is much dimmer and is used by females to choose a mate. But exactly how do female ostracods go about catching the moving and light-pulsing man of her dreams?

Scientists, Trevor Rivers of the University of Kansas and Jim Morin of Cornell University, set off to explore if female ostracods try to intercept the moving and pulsing males or if they just chase them. In order to conduct this experiment, immature female ostracods were collected off the shore of Southwater Caye in Belize. After catching the ostracods, females were put into tanks and raised to maturity, ensuring that all the females were sexually mature virgins. Rivers and Morin put an LED light behind the different tanks in order to mimic an actual mating display. The LED light looked like a string of Christmas lights pulsing from bottom to top, mimicking the males’ helical light display. In the control group, there was an LED light placed behind the tank, however it was turned off. The duo questioned whether or not the LED light show was able to mimic the display put on by male ostracods. Also, they questioned how females respond to the males’ display by measuring the height at which females intercepted the LED light, how straight of a line the female swam in, if the female swam at an angle, and what direction the female swam in. Check out a video here.

The scientists found that the LED light was able to mimic the helical phase that male ostracods put on well enough for the females to respond. Females in the control group merely swam at the same height, as there was no reason for her to waste her energy with no “male” around. However, females in the experimental group had to think on their feet to figure out where their male crush was heading. They swam directly toward but slightly above the “male” than when there was no “mate” around. If the female merely headed to the same spot where her “male” previously was, she would miss him. Instead, she had to anticipate where he was going next and head that direction.

What’s the moral of the story here? If you’re a female ostracod, your man will always be on the move, so you better have some gnarly geometry skills in order to track him down.


Work Cited:

Rivers, T., & Morin, J. (2013). Female ostracods respond to and intercept artificial conspecific male luminescent courtship displays Behavioral Ecology, 24 (4), 877-887 DOI: 10.1093/beheco/art022

How To Get Into An Animal Behavior Graduate Program: Preparing for Your Interview

Congratulations! You have been invited to interview for a chance to be a graduate student. …Now what?

Image from freedigitalphotos.net.

First of all, give yourself a pat on the back. Graduate student positions are highly competitive and as funding dries up, they are becoming even more so. Being invited to interview means that you have done all the right things to grab the attention of a Principal Investigator (P.I., i.e. the person that runs a research lab). At this point, the P.I. has already assessed your application and determined that you have the potential to be productive in his or her lab. Your primary job in this interview is to confirm this view. However, many people forget that interviews go two ways: Your second job in this interview is to assess whether this is the lab where you want to spend the next 4-8 years of your life.

A helpful way to think about interviews is from the perspective of the interviewer. What does a P.I. hope to do by interviewing prospective graduate candidates in the first place? Most P.I.s are limited in how much time they have for mentoring and how many resources they have to support students and their research interests. They want to know that the students that they accept will be motivated, capable, and realistic. They also want to know that anyone new to the lab will get along with current lab members. Ideally, new lab members would also bring in new energy and ideas. To gain insight about where you may fall with respect to these qualities, most interviews for graduate positions include a one-on-one chat with the head of the lab, social interactions with other lab members, and tours of the lab and parts of campus or the geographic area.

Your one-on-one interview with the P.I. is your primary time to convey your passion for what the research lab does and your motivation for being a part of it. This means that you need to do your homework beforehand: Read the lab website (if there is one) and know what the major topics of research are. Read several papers from the lab and have a sense of what techniques they use (The P.I. is usually listed as the last author of papers that are published by lab members). From what you have learned about the lab, have a few different ideas for projects you might be interested in working on if you were a student there. What qualities do you have and what experiences have you had that show that you would be capable to do such a project with adequate mentoring? If you can get the P.I. excited about an idea you pitch, you have a good chance of getting the spot. However, don’t get too attached to your research ideas: They may not be feasible for some reason or perhaps the P.I. only has funding for a student to work on a specific project, so you need to go in with a flexible mindset. You should also ask questions of your own during this time, both to show your serious interest and to assess if this lab and potential advisor are a good fit for you. Here are some questions you may want to ask:

1. I know you have done research on X, Y, and Z from reading your website and papers, but do you have any lines of research you are currently working on or plan to work on that you have not published yet?
2. How involved are you in helping your students choose their topics of study?
3. How do your students learn research techniques?
4. How are most students in your lab funded? (If you express a willingness to apply for your own funding, the P.I. will be impressed).
5. How long do most of your students take to get a degree?
6. Have any of your students left before completing their degree?

All of the lab members will try to assess how well you will likely fit in with the group. Don’t let this freak you out: Just be your natural self, but be careful which self you project: you don’t want to be the version of yourself that relaxes on the couch with friends slinging curse words like a drunken sailor (even if the other lab members are interacting this way with one another). Remember that you are meeting them for the first time, so be the friendly and slightly more formal version of your natural self that you present to Grandma or church. Also use this time to get the “real” scoop that you may not get directly from the P.I. Some good questions to ask lab members (when the P.I. is away) are:

1. How is the P.I. as a mentor? Have you or anyone else had any issues with the P.I.?
2. What are other lab members like?
3. What is it like to be a graduate student in this program?
4. What is the area like?
5. Where do graduate students live? What is typical rent like?
6. How hard is it to get funding as a R.A. (research assistant) or T.A. (teaching assistant)? How difficult is it to balance R.A. or T.A. responsibilities with classes and research?

Don’t forget that as the lab is trying to assess whether you would be a fit with them, you should assess whether they would be a fit for you. Are there opportunities to do research that you find interesting and to gain skills that will be useful to you? Is this a place and a lifestyle that you think you would be happy in for the next several years? And perhaps most importantly, does the P.I. have a personality and mentoring style that will help you grow as a person and as a scientist?

As for what to wear, dress business-casual and appropriate for the weather. There will likely be a lot of walking around, some outside. Scientists are a practical bunch and will not likely be impressed with your fancy outfit if it does not exhibit common sense. On the other hand, they will think you lack motivation if you show up in tattered jeans and a sweatshirt. Wear something semi-professional and comfortable.

Now get out there and knock their socks off!

For more advice on applying for graduate programs, go here.

When The Going Gets Tough, The Tough Become Babies

Today I am giving new young life to a post from 2012. You can find the original here.

We celebrate the New Year as a time of rebirth, renewal, and do-overs. We join gyms, swear off our bad habits, and promise to be better people. This is especially true for those of us that have had a rough 2015... Our 2016-version-of-us has got to be better, right? But what if you could get a real do-over? What if you could be a kid again, grow up again, and become a brand new person? As far-fetched as it may sound, some animals do exactly that.

Cnidarians (the "C" is silent) are a huge group of aquatic animals that includes jellyfish, corals, and anemones (like the one Nemo lived in - Yeah, that tentacled home was a living animal). They are named after prickly plants known as nettles, or cnides in Greek, and if you touch one you will quickly know why. Cnidarians, armed with stinging cells called nematocysts, sting at the slightest touch.

Jellyfish make up many of the cnidarian species, and they have been found in every ocean and at every depth. Some even live in freshwater. The "typical" jellyfish life cycle starts when eggs and sperm are released into the water and find one another. When they do, they form larvae, which you can think of as baby jellyfish. The larvae sink and settle on a hard surface, where they mature into polyps. These polyps are jellyfish in a juvenile stage. The polyps elongate and begin to bud off adult medusa, which are the bell-shaped blobs with tentacles that most of us think of when we think of a jellyfish. Medusa mature to become reproductive adult jellyfish.


The jellyfish life cycle by Zina Deretsky at the National Science Foundation (NSF). Image available at Wikimedia.

Larval and polyp jellyfish are much more resistant to harsh conditions then are medusa jellyfish. When life gets hard for a jellyfish, perhaps because of starvation, physical damage, temperature changes or salinity changes, those that are in the larval or polyp stages can often shrink and rest in a hibernation-like state while they wait for more favorable conditions. But in some species, young adult medusa can even regress back to the juvenile polyp stage. By reverting back to a juvenile stage, they have more protection from the challenging world around them.

In most cases, this reversal to a juvenile state can only happen in young medusa that have not yet developed their gonads. Thus, the onset of sexual reproduction (puberty, if you will) might be regarded as the point of no return in development. However, one species, called the immortal jellyfish, has shown that this rule can be broken.

As an adult medusa, the immortal jellyfish is a pea-sized jellyfish with a round bell, bright red stomach and anywhere from 8 to 90 tentacles. It is currently the only known animal that can regress from a fully reproductively mature adult into a juvenile polyp. If exposed to dangerous conditions, immortal jellyfish medusae completely reduce all of their medusa-specific organs and tissues and develop new polyp-specific tissues, essentially becoming kids again!

This figure from the Piraino et al. 2004 paper at the Canadian Journal of Zoology shows the life stages of the immortal jellyfish. The adult medusa is in panel (a). Panels (b) and (c) show the medusa tranforming to a ball-like blob as it reverts to a juvenile stage. The green stain in these panels shows the cells initiating this transformation. Panel (d) shows the remnant of a medussa, and the black arrow shows the stalk that is common in the polyp stage. Panel (e) shows the resulting juvenile polyp.

But wait! It gets better! Theoretically, if an animal can revert to a juvenile stage at any point in its adult life, it could attain immortality. But if that were true, they would have the classic immortality problem: These animals would reach such high populations they would saturate the world's oceans...And this may actually be happening.

Immortal jellyfish are thought to originally be from the Caribbean, but they have since been discovered worldwide and their populations seem to be growing. Likely, they are hitching rides in the ballast water that is sucked into cargo ships to provide stability. If this is true, the immortal jellyfish polyps could be attaching to the ships' hulls and settling in for a long voyage to a new home.

We don't yet know if the immortal jellyfish are actually immortal, but it is fun to consider that they might be (although they can still be killed by predators or viruses, so they're not invincible). And we can take inspiration from them: When the going gets tough, try reverting to your more resilient juvenile self, but be thankful you don't have to go through middle school again!

Happy New Year!

To learn more, check these out:

1. Piraino, S., De Vito, D., Schmich, J., Bouillon, J., & Boero, F. (2004). Reverse development in Cnidaria Canadian Journal of Zoology, 82 (11), 1748-1754 DOI: 10.1139/z04-174vv

2. Miglietta, M., & Lessios, H. (2008). A silent invasion Biological Invasions, 11 (4), 825-834 DOI: 10.1007/s10530-008-9296-0