Junior Explorer Club of Upper Arlington visits ant lab

How do animals communicate?

ant sketch

Morgan Oberweiser introducing animal sound activities to junior explorer club

Morgan Oberweiser introducing animal sound activities to junior explorer club

The Adams Ant Lab hosted elementary school children from the Junior Explorer Club of Upper Arlington. Recent graduate Mazie Davis and undergraduate students Andrew Mularo and Morgan Oberweiser put together a program to teach the little ones about various ways that animals communicate. First the students played a bioacoustics guessing game – they listened to some diverse audio recordings, courtesy of the Borror Lab of Bioacoustics, and tried to guess what animals they came from.

Can you tell which animals make these sounds? Look for the correct answers at the bottom of this post.

mystery sound 1:

mystery sound 2:

mystery sound 3:

Next the students learned about the use of coloration for communication. They observed camouflage in northern walking stick insects and African ghost mantises, as well as warning coloration in Peruvian black velvet stick insects and yellow banded poison dart frogs.

The last animal communication system we discussed was chemical communication. The students played a game in which they were each given a scented cotton ball (peppermint, almond, vanilla) and were tasked with sorting themselves into groups using only their noses. Then they compared their skills to those of our large Atta ant colony.

Ant colonies & fungus gardens in R Adams lab at OSU-MBD

Ant colonies & fungus gardens

The grand finale of the trip was a quick tour of the tetrapod collection lead by Dr. Katherine O’Brien. It was a joy to have such wonderful and inquisitive kids come to visit – we expect to see many of their excited faces return come next spring’s Open House (April 7, 2018)!

About the Author: Morgan Oberweiser is an undergraduate (Evolution and Ecology major) research assistant in Rachelle Adams‘ lab.

Answers to animal sound quiz: sound 1 = American alligator (chickadees scolding the alligator), sound 2 = Texas leafcutting ant, sound 3 = South American catfish

Why describing new species is exciting and important!

For many researchers describing a new species seems like a tedious task. The differences between species might not be obvious, and the language confusing and foreign. This fact became apparent to me when I first presented my work to the Ant Lab at the Museum of Biological Diversity (MBD). As I described subtle differences in morphology, a little spine here and the shape of a hair there, I could tell that I had lost my audience by the dulled looks on my lab mates faces. How could they not see the differences in these two species?

comparison of Trachymyrmex new species and T. zeteki

Fig. 1 – Trachymyrmex new species on the left and T. zeteki on the right

“Some key differentiating characters: The integument is granulose, spatulate bi-colored setae occur between the frontal carina, the scape extends past the occipital corners. This is compared to a weakly irrorate integument, simple bi-colored setae between the frontal carina, and the scape reaching the occipital corners.”

Fig. 2 – In case you are not familiar with the some terms used in describing ant species


Totally clear, right?

While the differences in characters that separate Trachymyrmex new species and T. zeteki, are exciting for me, it seems to bore people to death. After my presentation, I received very helpful constructive criticism from my lab group. They thought it was interesting but a lot of my presentation went over their heads. My advisor, Dr. Rachelle Adams (Assistant Professor in the Department of Evolution, Ecology and Organismal Biology), encouraged me to find a way to turn the jargon into something people can digest and appreciate. I am still working on that, and it is a challenge many researchers face.

Species descriptions are important and a necessary part of daily life

Hopefully your parents told you when you were younger, never eat mushrooms you find in the woods. Taxonomy helps us understand what kind of mushroom you found, if it is edible, or if it might seriously hurt you if you eat it. Mushrooms are a great example of why taxonomy is important. Scientists need to describe and name species so that others can learn which characteristics define a species. Then chemists can tell us which are toxic. This information communicated to the public can potentially save lives! Taxonomists donate representations of species in museums so that they can be compared by other scientists in the future. Aside from publishing their species description, they submit the specimen used to describe the new species, a type specimen. Anyone who works with any type of animal or plant should be submitting voucher specimens, physical specimens that serve as a basis of study, as representatives of their work.

Cody working at microscope

Fig. 2 – Photo courtesy of Plain Janell Photography

My Taxonomic Conundrum

While working on my species description, I reviewed all the literature that included T. zeteki. The 30 papers covered a number of areas such as fungus-growing ant genomes, mating systems, alarm pheromones, larvae development, and gut bacteria. Sadly, almost half of the papers do not mention depositing voucher specimens! Two articles deposited their DNA sequences as vouchers to a database for molecular data. Any research that uses DNA sequences has to submit DNA vouchers to that database; without it your work cannot get published. However, they do not have any physical vouchers linked to their sequences! This lack of physical vouchers was quite a surprise to me. The time I spent as an intern at the MBD Triplehorn Insect Collection, my advisors and other mentors strongly advocated the deposition of vouchers. Without being able to link your DNA sequence to a correctly identified organism, that DNA voucher loses its value. You cannot quickly identify an organism from DNA. Using morphology is the easiest way to do so! It seems many researchers don’t recognize the importance of vouchering and most non-taxonomic journals do not demand it. Research published without vouchers lacks reproducibility, an essential component of the scientific method.

In my research project, I am cleaning up the mess left behind from nearly twenty-years’ worth of poor vouchering and misidentification. I’m not only describing a new species and key characters that differentiate two cryptic species, I am listing all of the papers that have been published in the past twenty years using the names Trachymyrmex zeteki and Trachymyrmex cf. zeteki. By linking the new species description to these articles scientists can move forward knowing the proper identification of these hard-to-identify fungus-growing ants.

The deposition of vouchers should be required for all publications, and is crucial for, past, present, and future research in biology. In my undergraduate research, I discovered there is a disconnect between research museums like the MBD and many scientists. While I am still struggling to turn the technical jargon into information that can be swallowed by non-experts, there are discussions to be had about the importance of taxonomy as a cornerstone in biology.

If you want to learn more about fungus-growing ants and the importance of university research collections, come see us at the MBD Open House April 22, 10am – 4pm.

CodyCardenas, undergraduate student ant lab, EEOBAbout the Author: Cody R. Cardenas is a Senior Undergraduate student in Entomology  working in the Adams Ant Lab.

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The Science Behind an Ant Sting: Delivery, Function and Chemical Composition

To date, around 71% of all described ant species have been found to sting or spray secretions from their venom glands. Some spray acid such as Formica mound building ants (clip from Life in the Undergrowth – Supersocieties by David Attenborough):

while others inject venom like the red imported fire ant Solenopsis invicta (video by Brave Wilderness channel):

Still other species wipe or paint their victim with poison and can dispense it like a smelly gas into the air. The toxic cocktail of organic compounds that make up ant venom is diverse. The venom of some species contains peptides and proteins, but these molecules typically only constitute 0.1-5% of the total venom extract. Instead, many species of ants depend upon alkaloids, a group of organic compounds defined by a heterocyclic ring containing a nitrogen atom. First discovered in ants in 1970, a diversity of venom alkaloids has been found throughout the subfamily Myrmicinae, with six structural classes represented and various differences in the substituents or side chains attached to the main molecule.

Why study ant venom?

Venoms have been found throughout all major animal phyla and play important roles in a number of ecological interactions, especially in predator-prey relationships where they are used as offensive or defensive chemical weaponry. While the venom alkaloids of many ant species have been identified and characterized, the biological activities of these compounds have only been investigated in a minority of groups. Alkaloids are presently known to have adverse toxic effects on a range of organisms; for example, the major component of S. invicta venom has not only been shown to act as a toxin on predatory and prey animal taxa but also possesses herbicidal and antimicrobial properties. Additionally, some alkaloids have been demonstrated to be utilized in a non-toxic capacity and serve communicative functions as well.

One of the goals of the Adams Lab here at OSU is to understand the biological functions and properties of the various venomous alkaloids of ants, and an area of active research has been within the genus Megalomyrmex. Although the majority of species are free-living predators, some are social parasites that infiltrate the colonies of fungus-farming ants. They consume host brood and fungus garden by dominating the farmers with their alkaloidal weaponry. A well-documented example of this interspecific interaction has been between the parasitic Megalomyrmex symmetochus and its host Sericomyrmex amabilis, in which the venom of M. symmetochus is a crucial component in the aggressive interactions that take place throughout the establishment and maintenance of the host-parasite relationship.

During these aggressive interactions, M. symmetochus ants often use three main types of alkaloid dispensing behaviors: gaster flagging, side-swipe sting, and gaster-tuck sting.

ant behavior "Gaster flagging"

Gaster flagging

A) Gaster flagging is when M. symmetochus ants vibrate their gaster at approximately a 45-degree angle with a drop of alkaloid venom at the tip. This allows for the venom to be dispersed into the air at a low concentration, and is thought to be a warning to their host ants to deter them from attacking, acting as both a visual and chemical signal.

ant behavior "Side-swipe sting"

Side-swipe sting

B) Side-swipe sting is when M. symmetochus’ gaster is waved from the side towards the host, dispensing the venom directly onto the host ant.

ant behavior "Gaster-tuck sting"

Gaster-tuck sting

C) Gaster-tuck sting is when the gaster is tucked under the body in between the legs towards the host ant, dispensing venom directly onto the host (see illustrations below for a visual representation of these behaviors).

However, the interactions between these species are not always aggressive, and in some cases the M. symmetochus parasites act like mercenaries and protect their host from a more lethal ant species – watch them in action (video by Rachelle Adams, Assistant Professor in the OSU department of  EEOBiology):

Our future research will continue exploring ant venoms in a broader context. The Adams Lab will be traveling to Panama to collect and observe Megalomyrmex species in their natural habitats as well as conduct experiments to gain greater insight into their biology. Look for our future blogs from Gamboa, Panama at the Smithsonian Tropical Research Institute in May!

For a more in-depth look at the relationship between M. symmetochus and S. amabilis, check out Dr. Adams’ article in the USA Proceedings of the National Academy of Sciences entitled “Chemically armed mercenary ants protect fungus-farming societies.” And to learn more about the venom of the red imported fire ant Solenopsis invicta, watch this video by Eric Keller.

Visit us at the Museum of Biological Diversity’s Open House on April 22nd to learn more about our research! We will have live fungus-growing ants!

 

Acknowledgements: We would like to thank Rozlyn E. Haley for the ant illustrations.

Reference: Adams, R. M., Liberti, J., Illum, A. A., Jones, T. H., Nash, D. R., & Boomsma, J. J. (2013). Chemically armed mercenary ants protect fungus-farming societies. Proceedings of the National Academy of Sciences, 110(39), 15752-15757.

About the Authors: Conor Hogan is a graduate student in Rachelle Adams’ lab and Mazie Davis is an undergraduate student who did a research project on parasitic ant stinging behaviors in Rachelle Adams’ lab in 2016.

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Mites as parasitoids of invasive ants

Another post in our series Explaining Science – bringing scientific discoveries focused around biodiversity to your living room.


Ants are fascinating creatures, often living in large colonies. Some of you may be familiar with this behavior as a  nuisance in your home, e.g. with carpenter ants or fire ants. Ant biology and their way of social living fascinates researchers, and some of the ants’ behavior may be quite similar to what we see in our societies. Just recently a study reported how Gene-Modified Ants Shed Light on How Societies Are Organized. But did you know that these small ants can themselves become hosts for even smaller animals? Mites, in particular species in the genus Macrodinychus, have evolved to parasitize ants. They feast on the content of ant pupae, the larval stages of ants, to nourish their own development. “Vampire mites” is what Dr. Hans Klompen, acarologist and Professor in the department of Evolution, Ecology and Organismal Biology, calls them. By the way, the ant species these mites parasitize is called Longhorn crazy ant, an invasive ant species with a cool name.

Listen to an interview with Dr. Klompen about his recent publication in Scientific Reports “Macrodinychus mites as parasitoids of invasive ants: an overlooked parasitic association” and learn about “a bizarre little group of mites”” that he studies.

How does one find out about mites, often microscopical creatures, living on ants, in particular when you are a researcher based in Ohio while the ants live mainly in the tropics?

One needs good collaborators at El Colegio de la Frontera Sur (ECOSUR), Gabriela Perez-Lachaud and Jean-Paul Lachaud, who study ants and noticed mites parasitizing their study subjects.

How did the project of describing a new mite species evolve into more?

 

Macrodinychus multispinosus Sellnick larva

Macrodinychus multispinosus Sellnick larva

How often do these mites attack ants and which species of ants?

Longhorn crazy ant

Longhorn crazy ant, the host
(c) The photographer and www.antweb.org, CC BY-SA 3.0

 

 

Do the mites attack all different colonies of ants?

 

So what do we know about the life history of this mite whose developmental stages, its nymphs, feast on ant pupae? Find out more results from Dr. Klompen’s research on these mites in Friday’s post!

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Terms you may want to familiarize yourself with:

Mites are small arthropods, closely related spiders and scorpions, with two body regions, no antennae, and four pairs of legs as adults.

The life cycle of these mites is  composed of five active stages: egg, larva, protonymph, deutonymph, and adult

ventral – the underside of an animal, the belly

dorsal – the upper side of an animal, the back

 

Reference:

Lachaud, J. P., Klompen, H., & Pérez-Lachaud, G. (2016). Macrodinychus mites as parasitoids of invasive ants: an overlooked parasitic association. Scientific Reports, 6.
Dr. Hans Klompen, Professor EEOBiology at OSUAbout the Author: Dr. Hans Klompen is professor in the department of Evolution, Ecology and Organismal Biology and director of the Ohio State University Acarology Collection.
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