Research

Ohio Dragonfly Survey – Spring Training 2018

Last Thursday, MaLisa Spring, state coordinator of the Ohio Dragonfly Survey, gave the introduction to a series of talks about dragonflies and damselflies, how to identify them (Bob Glotzhober), how to photograph them (Jim McCormac) and how to report them on iNaturalist (Jim Lemon).

The audience was captivated by stories such as dragonflies being ferocious hunters, some have even been reported to prey on hummingbirds (albeit rarely).

On the other hand, watching dragonflies glide over open water on a warm summer day can be very peaceful and give us appreciation for their beauty and flying ability.

Bob Glotzhober even speculated that the origin of the shape of the Valentine’s heart can be found in the mating ritual of some dragonflies. What do you think?

So how does one identify a dragonfly?

And how do you distinguish a dragonfly from a damselfly?

But be careful, size is not the only difference and may be deceiving: in the tropics some damselflies grow to 7 inches in length!

If you want to learn more about dragonflies, visit the Ohio Dragonfly Survey website or attend the Odonata conference in June 22-24 2018 in Findlay, Ohio.

https://u.osu.edu/ohioodonatasurvey/2017/11/08/save-the-date-for-odo-con-18-june-22-24-2018/

To identify dragons and damsels in the field, we recommend that you download the ODNR guide (booklet pub 320).

If you enjoy fishing, you may catch a dragonfly in its larval stage and the Atlas of the dragonfly Larvae may help you identify it.

As always, feel free to post any questions right here on our blog.

About the Author:  Angelika Nelson is the curator of the Borror Laboratory of Bioacoustics and the social media manager for the museum.

Follow us on Facebook.

 

Explaining Science – plant genomics

Brandon Sinn performing molecular lab work

Brandon Sinn performing molecular lab work

Brandon Sinn, PhD graduate from the OSU herbarium, now a postdoctoral fellow at West Virginia University, recently published a paper on molecular work he did to better understand the evolution of genomes in Asarum (Aristolochiaceae), commonly known as wild ginger. The work was done in collaboration with Dylan Sedmak, an OSU undergraduate student, Lawrence Kelly, Associate VP of Science, New York Botanical Garden and John Freudenstein, Professor and Chair of EEOB and Brandon’s PhD advisor.

We interviewed Brandon to get a better understanding of his research findings:

Brandon: “Evolutionary relationships in the flowering plant genus Asarum served as the focus of my dissertation research, and I continue to study the group.  In this particular project we studied six Asarum species, which each represent one of the six major evolutionary lineages within the genus.

Flowers of some Asarum species found in southern Appalachians

Flowers of some Asarum species found in the southern Appalachians

Asarum is a poorly-understood genus of approximately 115 species found in temperate forests across Asia and North America. Some Asarum species are common and widespread across the continents where they are found, while the majority have highly restricted ranges – for example, one species is known only from a single gorge in North Carolina and others are found in only a few counties in the southeastern United States.

During the course of sequencing DNA for my dissertation research, I realized that the genes of some Asarum species were not in the expected order. This departure from expectation was surprising, since the clade, or evolutionary neighborhood, that Asarum belongs to is very old and had been partially characterized as having slowly-evolving and highly conserved genomes. For example, the genome of another member of the same clade has been called a “fossil” genome. It was because of this unexpected observation that we decided to sequence complete genomes from one species from each of Asarum lineage. ”

This lead to the following research questions: Note: A plastome is the genome of a plastid, the organelle responsible for photosynthesis in plants.

1) Have the plastomes of all Asarum species been destabilized and their gene order rearranged?

2) Is the plastome of Saruma henryi (commonly called upright wild ginger), the closest relative of Asarum, of typical arrangement or is it more like that of Asarum?

3) Can we understand how the ordinarily highly conserved and stable plastomes become destabilized by comparing the plastomes of many Asarum species to that of Saruma henryi?

Saruma henryi, a flowering plant in the family Aristolochiaceae, endemic to China

What should we know to understand this research?

Brandon: “Each plant cell contains at least one copy of three distinct genomes. It is easy to imagine that each cell has a copy of the plant’s genome, but many people forget that two types of plant organelles, mitochondria and plastids, also have their own genomes. Plastids, from which chloroplasts develop, have a very small genome that is relatively easy to completely sequence and the sequence of more than 2,000 are publicly available today. The sequencing of thousands of plastomes has resulted in several general trends: 1) plastomes change more slowly than the plant’s own genome; 2) the plastome is made up of three functional regions, the small single copy, large single copy, and inverted repeat regions; 3) the physical order of genes is highly conserved across even distantly related species; 4) there is very strong selective pressure on the preservation of photosynthesis, which most likely constrains the evolution of plastomes in green plants. Our knowledge of the typical layout of the plastid genome, or plastome, has long been relied upon to sequence DNA in order to study plant evolutionary relationships. Traditional DNA sequencing techniques require prior knowledge of the order of genes or regions of a genome. If this order is not as predicted, then the DNA sequencing will fail.”

What method did you use to study your research question?

Brandon: “For this study, we sequenced entire plastomes from six Asarum species and that of Saruma henryi, the closest relative of Asarum. Since traditional DNA sequencing is not useful in destabilized and dynamically rearranged genomes, and we wanted to sequence entire plastomes that we hypothesized were rearranged, we needed to use a technology called massively parallel sequencing. A major advantage of massively parallel sequencing is that a researcher can extract DNA from a tissue, break the DNA into short pieces, and simultaneously sequence all of these fragments without prior knowledge of their physical relationship to one another. The resulting millions of DNA sequences are then assembled, much like a puzzle, using specialized software. The assembled  plastomes can then be compared.”

Brandon explains one of the key figures in his manuscript:

A cruciform DNA structure that has likely destabilized a region of the plastome in Asarum species. Structure courtesy of Eric Knox.

A cruciform DNA structure that has likely destabilized a region of the plastome in Asarum species. The end of the ndhF gene is shown in red. Structure courtesy of Eric Knox.

DNA is made of only four chemicals (which we abbreviate as the letters A, T, C and G) and is not entirely unlike a spiral staircase, where each handrail is a string of these letters. Holding this structure together are bonds that form between certain letters – A-T and G-C. We call these letters nucleotides. Sometimes the nucleotides making up DNA cause the molecule to form complex shapes, such as the cruciform structure shown here. Cruciform, or cross shaped, DNA structures form when the same nucleotides are repeated very close to one another, which is depicted in the vertical “stems”.

plastomes

Cruciform DNA structures can be difficult for the molecular machinery in cells to work with. For example, sometimes molecules that interact with DNA get stuck on the stems, and these structures compromise the integrity of the DNA molecule. When these structures break, which you can imagine by separating the red and black halves of DNA for Saruma henryi, the cell tries to put them back together. But, repairing DNA does not always work perfectly. The results of our research suggest that faulty repairs made to this DNA structure throughout the plastomes of Asarum species have resulted in varying degrees of DNA duplication. Notice that the ndhF gene (shown in red) is typically at one end of the small single copy region, as shown on the Saruma henryi plastome. In Asarum, this gene often has a long stretch of nucleotides that can be “pasted before or after it. In other Asarum plastomes, such as Asarum canadense, we find that all of the small single copy region has been duplicated. The duplication of the formerly single copy region is most likely due to faulty repair of the cruciform DNA structure, where identical strings of nucleotides close to one another led to bonding of two identical DNA regions (as seen in the Asarum canadense cruciform structure).”

Why is this research important?

Brandon: “When you learn about DNA in high school science classes, everything sounds very concrete and well understood, but even gene function in humans is not exhaustively understood. Our basic knowledge about how genes and genomes evolve is in a constant state of improvement. This knowledge is necessary for future breakthroughs in genome engineering, evolutionary and conservation biology, and improving genome stability.  Just as it is important to understand biodiversity at the level of species, it is equally important to understand genomic diversity – the content and structure of genomes, in order to understand how mutations in particular regions of genomes can lead to genome-scale changes over deep time and how these changes affect evolutionary lineages.”

What should you take away from these findings?

1) Just because a species is a member of a very old evolutionary lineage, we should not expect that it is a living fossil and that its genome has changed little.

2) A plastome can function even when gene order is changed and more than half of its genes are present more than once.

3) Small, likely randomly generated repetitive motifs in DNA sequence that is not part of a gene can decrease genome stability, and lead to genome rearrangement and gene duplication.

*******************************************************

Wow, we are now certainly asking questions and getting answers with new techniques that we could not have imagined decades ago. If you want to follow Brandon’s further research, click here.

About the Authors: Brandon Sinn photoBrandon Sinn earned his Ph.D. in 2015 from the Department of Evolution, Ecology and Organismal Biology, where he was a member of the Freudenstein Lab in the Museum of Biological Diversity. Brandon has held a postdoctoral research position at the Pfizer Plant Research Laboratory of the New York Botanical Garden, where he worked on the Planteome Project. He is currently a postdoctoral fellow in the Department of Biology of West Virginia University where he studies orchid genome evolution as a member of the Barrett Lab.

Angelika Nelson is the curator of the Borror Laboratory of Bioacoustics and the social media manager for the museum.

Follow us also on Facebook.

 

 

Reference:
Sinn, B. T., Sedmak, D. D., Kelly, L. M., & Freudenstein, J. V. (2018). Total duplication of the small single copy region in the angiosperm plastome: Rearrangement and inverted repeat instability in Asarum. American journal of botany, 105(1), 71-84.

Staff spotlight – Jacqualyn Halmbacher

Jacqualyn Halmbacher, Research Associate at The Columbus Zoo and Aquarium Freshwater Mussel Conservation and Research Center, gave us an inside look on her research regarding freshwater mussels for this month’s staff spotlight.

Freshwater Mussel Conservation and Research Center
Jacqualyn collecting mussels
Jacqualyn Halmbacher

Hilary: “Tell us about yourself!”

Jacqualyn: “I graduated from Ohio University in 2012 with a degree in Freshwater, Marine, and Environmental Biology. After I graduated, I worked in a seasonal position at the Columbus Zoo for five months, before eventually being hired by The Ohio State University as a Research Assistant in  2012. Since 2016 I have been a Research Associate at the Freshwater Mussel Conservation and Research Center.”

Hilary: “What is a freshwater mussel?”

Jacqualyn: “Freshwater mussels are mollusks that are similar to their cousins, clams and oysters.  Mussels are bivalves, meaning that they have two shells that are held together by two adductor muscles and they feed by filtering food such as zooplankton, detritus, algae, and bacteria from the water with their gills. Mussels are an ancient species, actually being traced back to the Triassic Period – 250 million years ago! They’re found on every continent except Antarctica and one third of the world’s mussels are found in North America, with about 80 species of mussels in Ohio alone – with more species found in Little Darby Creek than all of Australian and European species combined!”

Giant floater Pyganodon grandis
juvenile wavy-rayed Lampmussel Lampsilis luteola

Hilary: “Can you tell us more about the facility?”

Jacqualyn: “The Columbus Zoo and Aquarium Freshwater Mussel Conservation and Research Center is a research and educational facility that’s dedicated to freshwater mussels and other freshwater organisms. Animals we house in this facility are for research purposes and will be sent back to the river systems that they came from. Some stay here long-term. Also, another large portion of the animals housed in this facility are for host work, which is important in propagation and knowing where the reared mussels should be released.”

27 river tanks housing 40 species of freshwater mussels

Hilary: “How does the life cycle of a mussel work?”

Jacqualyn: “Freshwater mussels have a unique life cycle that includes a larval stage where they parasitize a fish. Once a female mussel’s eggs have been fertilized, they develop into larvae called glochidia, which will attach and develop on the gills of fish once the female mussel releases them into the water. They will remain on the gills of fish for up to two weeks, where they will receive the nutrients necessary to grow and develop as they metamorphose into juveniles. Once the full transformation is complete, they will leave the host to live independent lives. What I’m doing in my current research with in vitro is simulating the conditions that the glochidia experience when they are on a host fish.”

 

Thousands of larval mussels (Pyganodon grandis) in culture medium
Preparing petri dishes for incubation

Hilary: “Propagation? Can you tell us more about this?”

Jacqualyn: “We propagate species naturally by using host fish, but recently we have been working on propagating them artificially in vitro. Freshwater in vitro is accomplished using cell culture techniques, which is removing cells or tissues from an animal or plant and placing them in an artificial environment for survival. The requirements for mussel survival include an environment with controlled temperature, maintaining a particular pH, osmolality, and a growth medium. The culture medium is generally composed of amino acids, vitamins, glucose, salts, proteins, hormones, growth factors, and antibiotics.”

 

Host fish housed within the facility
juvenile Pyganodon grandis– day 1 (filtering algae)
larval Lampsilis ovata– day 18 (in media)

Hilary: “Why is this important to study?”

Jacqualyn: “It gives us the ability to produce more juveniles in one dish than what we could get from several fish, while simultaneously allowing us to see mussel growth and development. Overall, studying mussel growth and development allows us to create successful conditions for breeding and conservation efforts for mussels, which in turn also helps us better protect their freshwater environment. 70% of mussel species are endangered and 37 species of mussels are extinct. Such species loss may have cascading effects through entire stream food webs, so the research we’re undertaking is important to protecting entire stream ecosystems.”

Hilary: “What projects are you working on now?”

Jacqualyn: “We have a propagation project going on in Illinois in conjunction with BP to propagate and release federal and state endangered species in the Kankakee River. I’m also trying to improve mussel rearing methods.”

Hilary: “What’s your favorite part about working at the facility?”

Jacqualyn: “The challenges that the research presents. There is constantly a new problem that needs to be solved in order to move forward. And I love the new microscope we have! I’ve been able to focus on details that you would never even realize were there.”

Hilary: “Have you made any recent discoveries?”

Jacqualyn: A personal accomplishment of mine is using in vitro to propagate mussels. I know that other researchers have been successful with it, but one thing that I’ve learned is that reading a research paper about an experiment and actually trying to duplicate it is something completely different. There are just so many components involved and so many things that happen that you just don’t account for until you’re in the middle of it.

poster - Meet Dr. Tom Watters: mussel man

If you want to learn more about freshwater mussels in Ohio and how to identify them, consider attending one of the mussel ID workshops regularly held at the Museum of Biological Diversity. Please contact Tom Watters, curator of mollusks, directly.

 

Hilary HirtleAbout the Author: Hilary Hirtle is the Faculty Affairs Coordinator at the OSU Department of Family Medicine; her interest in natural history brings her to the museum to interview faculty and staff and use her creative writing skills to report about her experiences.

Staff spotlight – Scott Glasmeyer

We met up with Scott Glassmeyer, a student research assistant in the Fish Division, to get an inside view on his role in the Museum of Biological Diversity.

Scott Glassmeyer holding a Rock Bass (fish)Hilary: “What is your major?”

Scott: “My major is Forestry, Fisheries, and Wildlife, with a specialization in Fisheries and Aquatic Science. I’d always loved fish since I was a kid and before I got into this program, I didn’t know that you could go to college to study fish, or do anything relevant with fish in a job, besides working to commercially collect fish. So, I did research to see if there were any higher education programs that involved learning about fish and aquatics and I found that Ohio State had this program.”

Hilary: “How long have you been a student research assistant in the Fish Division?”

Scott: “Since spring of 2016, but I started as a volunteer in January of 2016 where my primary role was to take older jars containing fish specimens and place them in new ethanol, to better preserve the fish.”

several fish in ethanol in glass jar

Fish in ethanol

Hilary:  “What is the mission of the Fish Divsion?”

Scott: “To preserve historical records of species of fish for future reference and overall long-term data collection and education. It’s a way to validate that this species of fish was recorded in a particular area and a specific species was recorded in general, as fish get misidentified a lot. So it improves a lot of accuracy regarding records.”

Hilary: “What fish are housed here?”

Scott: “Mostly Ohio fish, but we have some from the entire 50 states as well. There are also some fish species from other countries, some saltwater fish, and some aquarium fish here as well.”

Hilary: “Are the specimens here largely donated?”

Scott: “A lot of the specimens are collected through the museum, as well as the Ohio EPA. The Ohio EPA has a division that monitors streams and stream quality statewide and they will collect fish in the process and send them to us.”

collecting fish with seine nets

Staff collecting fish with seine nets

 

Hilary: “How are the fish preserved?”

Scott: “The way the preservation process works is that you put the fish specimens in formaldehyde for a certain amount of time, then you place them in water for about a day, before you start adding the ethanol bit by bit, as you slowly add larger amounts of ethanol to build up the tolerance – and that’s what they stay in. It takes up to a week and a half to two weeks to put them in this preserved state.”

Hilary: “Why is it important to study these fish?”

Scott: “It’s really important to study these fish because it helps you not only understand the water quality of their habitat, but also the intrinsic value of their ecosystems. For example, if you have a stream that’s just concrete because it was filled in, this could possibly only allow for about 5 species of fish to live there, whereas before, when the stream had natural morphological features and geological shapes, there were a lot more species of fish living within in this habitat.”

“A good example of this is from about 6 or 7 years ago, when the 5th Avenue Dam along the Olentangy River near campus was removed. Trees, plants, and wetlands were added along the bank and this natural state contributed to the value of the stream, not just for people, but for the fish as well, as this improved quality increased the level of biodiversity within in and around the river.”

Scott Glassmeyer holding Giant bottlebrush crayfish

Scott Glassmeyer holding a Giant bottlebrush crayfish

Hilary: “What’s your favorite part about working in the Fish Division?”

Scott: “I love going outside, putting waders on, getting in the stream and finding fish. You can read all you want about how healthy a stream is, but when you go out there and you see the biodiversity in the water as you collect data, you can tell just how healthy the water is and it’s wonderful.”

“I also really like the people who work here with me. Everyone’s very patient here and they take the time to help you out as your learning, which is really nice as learning to identify fish for the first time involves a learning curve.”

Hilary: “What is a project that you’re working on now?”

Scott: “I’ve been editing photographs of fish taken by Brian (my colleague who is the Sampling Coordinator in the Fish Division) and getting them ready to be put into the field guide version of the Fishes of Ohio.”

book cover Fishes of Ohio by Milton B Trautman

“The Fishes of Ohio was a guide written in the ‘50s, by Trautman, and then it was revised in the ‘80s by Trautman, and so what we’re working on now would be the next revision. There’s around 190 species or so of fish in Ohio, including invasive species and extinct species, so we’ve been photographing each species listed in the field guide, oftentimes with more than one picture, as you’re taking pictures of what you use to identify them. For example, for some of the sucker species of fish, you have to show the mouth, as that helps with identification. So with these species, there’s some photographs detailing the mouth from underneath, and there’s some side photographs, so that you can see the shape of the head and the mouth from the side for identification.”

 

Hilary: “Do you photograph the fish in their habitat?”

Scott: “It depends. There was one species of fish where we went out during their spawning season and had the tank set up to photograph them. We caught them, put them in the tank, and took a picture quickly, as they can lose their colors pretty fast. If a fish we find doesn’t have a particular color, we take them, put them in a cooler with an aerator, and take them away from location to photograph them. It’s a time consuming process, with the drive to the specimen’s location, the set-up, hours of wading for fish, and then the tear-down of equipment and the drive back from the site, so taking them away to photograph them can be easier than doing it onsite.

Hilary: “You said that fish lose their colors – what does that mean?”

Scott: “Fish have pigments in their skin, underneath their scales. There’s a lot of colorful fish in Ohio, like darters and minnows, that will have breeding colors and so, during certain times of the year and certain times of the day (or even after they eat) they’ll get a lot of pigment and colors in them. And even if they’re not a colorful fish, their colors can change. For example, you can take a large mouth bass that has some pattern to it and put it into a bucket that’s really light and pull the fish out ten minutes later, and the fish will look really pale. But if you put it in a dark cooler, the fish is going to remain dark and have more color. The stress levels will impact them.”

Hilary: “Do you have a favorite fish species?”

Scott: “This question’s hard. So, my answer changes every month when I discover a new fish, but currently my favorite fish is the Common Dolphin Fish, or the Mahi-mahi. There’s a reason why I like it: So, over 50% of its diet is flying fish, and that’s pretty cool to me. Also, its maximum life span is five years. A marlin or a swordfish can live to be about 27 years of age, and a medium sized Ohio fish species can live to about 15 years. However, the Dolphin Fish lives such a short span of time compared to these fish, yet it grows extremely quickly, as they get up to 36 pounds in 8 months. And it’s really fast too, swimming speeds up to 50 miles an hour.”

Common Dolphin Fish, or Mahi-mahi

Hilary: “With all of your experience and studies, what do you hope to do in the future?”

Scott: “I’d love to work as a fisheries biologist, working for the environment. It’s challenging to get in those types of roles, as they’re very competitive, but I’m going to try.”

 

Hilary HirtleAbout the Author: Hilary Hirtle is the Faculty Affairs Coordinator at the OSU Department of Family Medicine; her interest in natural history brings her to the museum to interview faculty and staff and use her creative writing skills to report about her experiences.

Explaining Science – Gene flow among song dialects

Today Kandace Glanville, an OSU Forestry Fisheries & Wildlife major and student assistant in the Borror Laboratory of Bioacoustics, talks with Angelika Nelson, Curator of the Borror Lab, about a recent research publication in the journal Ethology. The study is entitled “High levels of gene flow among song dialect populations of the Puget Sound white-crowned sparrow”.

Find out why we studied the White-crowned Sparrow Zonotrichia leucophrys pugetensis to investigate gene flow among song dialects:

The research aimed to investigate a correlation between behavioral and genetic differentiation:

Song dialects of White-crowned Sparrows along the Pacific northwest coast
Study site in Bandon, Oregon
Angelika Nelson banding a White-crowned Sparrow in the field

Our research built on knowledge from previous studies and used samples that were collected previously:

Angelika working in the molecular lab
Size differences among peaks of microsatellites, nucleotide tandem repeats in DNA sequences
A strand of DNA suspended in buffer

We found gene flow among bird populations that differ in song dialects; this may demonstrate dispersal of young birds across dialect borders:

Our findings are consistent with most studies to date of song and population structure within songbirds. The processes of song learning and dispersal mean that vocalizations are free to vary independently of patterns of divergence in neutral genetic markers.

Reference:
Poesel, Angelika, Anthony C. Fries, Lisa Miller, H. Lisle Gibbs, Jill A. Soha, and Douglas A. Nelson. “High levels of gene flow among song dialect populations of the Puget Sound white‐crowned sparrow.” Ethology 123, no. 9 (2017): 581-592.

 

About the Author: Angelika Nelson is the curator of the Borror Laboratory of Bioacoustics and the social media manager for the Museum of Biodiversity.

Explaining Science – vermiform mites

You have heard of mites – minute arachnids that have four pairs of legs when adult, are related to the ticks and live in the soil, though some are parasitic on plants or animals. But what are vermiform mites? Maybe you have heard of vermi-compost, a composting technique that uses worms (like your earthworm in the garden) to decompose organic matter. So vermiform mites are mites with a body shape like a worm:

worm-shaped nematalycid Osperalycus

Why are they shaped like a worm, you may ask – To find out more I interviewed Samuel Bolton, former PhD student in the acarology collection at our museum, now Curator of Mites at the Florida State Collection of Arthropods. Sam’s main research interest is in mites that live on plants and in the soil, especially Endeostigmata, a very ancient group of mites that dates back around 400 million years, before there were any trees or forests. Sam’s PhD research with Dr. Hans Klompen here at OSU, was focused on a small family (only five described species) of worm-like mites, called Nematalycidae.

side note: You may have heard of Sam’s research in 2014 when he discovered a new species of mite, not in a far-away country, but across the road from his work place in the museum.

When Sam started his research it was not clear where these worm-like mites in the family Nematalycidae belong in the tree of life. To find out Sam studied several morphological characters of Nematalycidae and other mites. He focused in particular on the mouth-parts of this group. As he learned more about the mouth-parts of this family, he found evidence that they are closely related to another lineage of worm-like mites, the gall mites (Eriophyoidea). Eriophyoidea have a sheath that wraps up a large bundle of stylets. They use these stylets to pierce plant cells, inject saliva into them and suck cell sap.
Although Nematalycidae don’t have stylets, one genus has a very rudimentary type of sheath that extends around part of the pincer-like structures that have been modified into stylets in Eriophyoidea.

So what did Sam and his co-authors discover?

“.. Not only are gall mites the closest related group to Nematalycidae, but the results of our phylogenetic analysis places them within Nematalycidae. This suggests that gall mites are an unusual group of nematalycids that have adapted to feeding and living on plants. Gall mites use their worm-like body in a completely different way from Nematalycidae, which live in deep soil. But both lineages appear to use their worm-like bodies to move around in confined spaces: gall mites can live in the confined spaces in galls, under the epidermis (skin), and in between densely packed trichomes on the surface of leaves;  Nematalycidae live in the tight spaces between the densely packed mineral particles deep in the soil.”

This research potentially increases the size of Sam’s family of expertise, Nematalycidae, from 5 species to 5,000 species. We have yet to confirm this discovery, but it is highly likely that gall mites are closely related to Nematalycidae, even if they are not descended from Nematalycidae. This is interesting because it shows that the worm-like body form evolved less frequently than we thought. This discovery also provides an interesting clue about how gall mites may have originated to become parasites. They may have started out in deep soil as highly elongated mites. When they began feeding on plants, they may have used their worm-shaped bodies to live underneath the epidermis of plants. As they diversified, many of them became shorter and more compact in body shape.

I wish I could tell you now to go out and look for these oddly shaped mites yourself, but you really need a microscope. Eriophyoid mites are minute, averaging 100 to 500 μm in length. For your reference, an average human hair has a diameter of 100 microns.

eriophyoid Aceria anthocoptes

Reference:

Bolton, S. J., Chetverikov, P. E., & Klompen, H. (2017). Morphological support for a clade comprising two vermiform mite lineages: Eriophyoidea (Acariformes) and Nematalycidae (Acariformes). Systematic and Applied Acarology, 22(8), 1096-1131.

 

About the Authors: Angelika Nelson, curator of the Borror Laboratory of Bioacoustics, interviewed Samuel Bolton, former PhD graduate student in the OSU Acarology lab, now Curator of Mites at the Florida State Collection of Arthropods, in the Florida Department of Agriculture and Consumer Services’ Division of Plant Industry.

 

Explaining Science – taxonomy of parasitoid wasps

Professor Norm Johnson, Director of our C.A. Triplehorn Insect Collection, studies systematics of parasitoid wasps and so do his students. Graduate student Elijah Talamas collected many insect specimens during his PhD work at Ohio State and revised several taxa. Recently he published a photographic catalog of some primary types of parasitoid wasps in the large insect order Hymenoptera.

samurai wasp, Trissolcus japonicus
Trissolcus euschisti, an egg‐parasitoid of stink bugs

I contacted Elijah in his current position at the The Florida Department of Agriculture and Consumer Service and asked him to give us some insights into his life as a researcher. He recently published results from work he did as a a postdoctoral fellow for the U.S. Department of Agriculture at the National Museum of Natural History in Washington DC:

Elijah TalamasElijah: “I am the curator of Hymenoptera (bees, ants and wasps) at the Florida State Collection of Arthropods, which is part of the Florida Department of Agriculture and Consumer Services. I have broad interests in the taxonomy, morphology, and evolution of platygastroid wasps, especially groups with potential for biological control. I was trained by Dr. Norman Johnson at The Ohio State University, and maintain active collaboration with him and members of his lab.”

Angelika: “What species did you study?”

Elijah: “As a taxonomist, I study many species and genera in the superfamily Platygastroidea. These are parasitoid wasps that require development in a host to complete their life cycle, i.e. their larvae live as parasites that eventually kill their hosts. The past few years have focused on the genus Trissolcus which are parasitoids of stink bug eggs.”

(Angelika’s note: You may recall that the brown marmorated stink bug is an invasive species from Asia, now found in the eastern half of the U.S., as well as California, Oregon, Washington, Arizona, New Mexico and Texas. You may have seen one in your home, especially in late fall when they are looking for a sheltered place to overwinter)

Angelika: “What was your research questions in this particular study?”

Elijah: “A typical taxonomic project will “revise” a genus and involves many questions: What are the characters that define the genus? How many species does it contain and how do we identify them? The separation of organisms into species is the foundation of organismal biology and this is one of the jobs of a taxonomist.”

brown marmorated stink bugAngelika: “What do we know already, and why is it important to know this?”

Elijah: “We know that many parasitoid wasps attack the eggs of agricultural pests. This is important because they are often the best, and sometimes only solution to control numbers. The invasive brown marmorated stink bug is an invasive pest that can be found in Ohio, and it is not controlled by natural enemies in the United States. However, there are parasitoid wasps in its native distribution in Asia that kill the stink bugs’ eggs very efficiently. Biological control research about these wasps requires thorough study of their morphology to ensure that
species are properly identified.”

Angelika: “How did you study this question?”

Elijah: “I study parasitoid wasps by examining them under a microscope, documenting their anatomical structures, and the variability that can occur within a species. This often requires examination of specimens from all over the  world, and sometimes international travel is required to access specimens in foreign institutions and to collect fresh material. I rely heavily on photography to document and share information about these wasps, but I also use other techniques, including scanning electron microscopy and analysis of DNA.”

When looking at detailed features one may notice that some of them are different from how they were originally described and the specimen may be more closely related to to another group of specimens. This means that sometimes the classification of the species needs to be revised and renamed to reflect these new relationships. For example, in the figures below you can see the holotype, the specimen that was used to describe the species Psilanteris nigriclavata. This species was originally described with the name Opisthacantha nigiclavatus in 1905. The specimen was embedded in glue, which obscured some of its diagnostic characters and hampered a clear assessment of its identity. As part of this project, Elijah dissolved some of the glue and determined that it shared characteristics with other species in the genus Psilanteris. Thus this species was moved to this genus and now operates under the name Psilanteris nigriclavata.

62 head, mesosoma, metasoma, lateral view; 63 head and mesosoma, anterodorsal view (sk=skaphion); 64 head and mesosoma, lateral view. Scale bars in millimeters.

Angelika:  “Why is this research important?”

Elijah: “Taxonomy informs us about many aspects of the biological world. It is the science that reveals the planet’s biological diversity and discovers the evolutionary relationships between organisms. It enables other disciplines to identify organisms for the studies of behavior and ecology, and applications with large scale societal impact, such as biological control of invasive pests.”

Angelika: “What do you hope to have achieved with this study?”

Elijah: “For parasitoid wasps in the superfamily Platygastroidea, this study provides photographs of all holotype specimens in the National Musuem of Natural History and makes them freely available online. Taxonomists all over the world now have immediate access to these specimens through the internet, enabling them to make better informed decisions for classification, and more refined hypotheses about evolution.”

Let us know if you have any questions, we would like to hear form you!

****************************************

Some explanations you may find helpful:

Anterodorsal means in front and toward the back.

A holotype is a single type specimen upon which the description and name of a new species is based.

Lateral means from the side.

The body of arthropods is composed of three parts, from front to back, the prosoma, mesosoma, metasoma.

A parasitoid is an insect whose larvae live as parasites that eventually kill their hosts.

Superfamily is an intermediate classification rank directly above family and might contain one or more related families. For example, Muroidea, a superfamily of rodents, contains six families of rats, mice, hamsters and gerbils. Taxonomists use several levels to classify living things. They follow the International Code of Zoological Nomenclature which specifically mentions superfamily, family, subfamily, tribe, subtribe, genus, subgenus, species, subspecies.

Reference: Talamas, E. J., Thompson, J., Cutler, A., Schoenberger, S. F., Cuminale, A., Jung, T., … & Alvarez, E. (2017). An online photographic catalog of primary types of Platygastroidea (Hymenoptera) in the National Museum of Natural History, Smithsonian Institution. Journal of Hymenoptera Research, 56, 187.

About the Author: Angelika Nelson is the curator of the Borror Laboratory of Bioacoustics and the Outreach and social media manager for the museum. Here she interviewed Elijah Talamas, currently Postdoctoral researcher with the U.S. Department of Agriculture at the National Museum of Natural History, Smithsonian Institution in Washington DC.

Summer in the field

This is the time when many students and faculty spend their days in the field doing research or attending conferences and meetings where they present their latest research results. Follow us on social media #ASCinthefield. We will not post here until the beginning of classes on August 22.

Have a great summer!

 

Squirreling in the Pacific Northwest

You may have heard that researchers discovered a new species of flying squirrel. These squirrels had lived in plain sight for decades but only recently did Brian Arbogast and colleagues investigate the DNA of some of these animals. Their findings were revealing: The Pacific squirrels cluster separately from the northern and southern flying squirrel. The researchers analyzed mitochondrial DNA as well as microsatellite data to reveal this new evolutionary relationship.

Note: Mitochondrial DNA and microsatellites are parts of a species’ genome that are regularly used to construct evolutionary trees. In addition to the DNA in every cell’s nucleus in our body, mitochondria, the energy powerhouses in our cells, have their own genome. This mitochondrial genome is relatively small, is inherited from the mother only and has relatively high mutation rates. It is like a small clonal lineage within an organism which makes it ideal for evolutionary studies.   Microsatellites are short sequence repeats in the nuclear genome that do not produce proteins. Thus they are free to mutate at a higher rate than coding sequences – mutations will not mess up protein production- and they frequently vary in length and thus reveal relationships among organisms. 

Flying squirrel specimens from the Burke Museum’s collection were used to help identify the new species, Humboldt’s flying squirrel. Credit: Burke Museum of Natural History & Culture
The Humboldt’s flying squirrel found in the Pacific Northwest; Photograph by Nick Kerhoulas

A few weeks ago, before this study was published, 2 species of flying squirrels were considered to exist in North America, the northern and the southern flying squirrel. Here in Ohio the northern flying squirrels is resident – it is nocturnal though, that’s why you probably have not seen one yet.

Map showing distribution of now 3 species of flying squirrels

Map showing distribution of now 3 species of flying squirrels

DNA analysis showed that the coastal squirrels in Washington and Oregon are distinct from their northerly relatives and that they actually only co-occur with them at 3 sites in the Pacific Northwest. Northern and the newly described Humboldt’s flying squirrel do not interbreed at these sites. By the way, the researchers named the new species Glaucomys oregonensis because the specimen that was used to describe the species was collected in Oregon.

You may recall from a previous post, that Dr. Andreas Chavez in our department of EEOB studies relationships among squirrels in a different genus, Tamiasciurus, the red squirrel T. hudsonicus and the Douglas squirrel T. douglasii. These two species share habitat in the Pacific Northwest and they do hybridize.

Dr. Chavez was not available for an interview for his thoughts on the new species description of flying squirrels, because he is currently pursuing his own fieldwork in the Pacific Northwest. He and his field assistant Stephanie Malinich are collecting data to better understand the hybrid zone dynamics between the Douglas and red squirrel.

We will give you an update on Dr. Chavez’ research once he returns.

About the Author: Angelika Nelson is the curator of the Borror Laboratory of Bioacoustics and writing this post for Stephanie Malinich, collection manager of the tetrapods collection. Stephanie is currently doing fieldwork on the red and the Douglas squirrel in the Pacific Northwest.

Songs on both sides of the Atlantic

Like every year I will leave for Hog Island, Maine tomorrow morning. I will teach at two of the Audubon summer camps that have been held on the island almost every summer since 1936. You may recall this from my previous post.

This year I am particularly excited to watch birds along the Atlantic coast as I just returned from a trip to Ireland, on the other side of the Atlantic ocean. There I spotted birds of several species that also occur along the US coast. I doubt that the birds themselves make the crossing, but members of their species reside and breed on both sides of the Atlantic.

Rathlin Island

So which birds are we talking about? In Europe we visited Rathlin island, a small island off the coast of Northern Ireland, where we watched Atlantic Puffins Fratercula arctica, Razorbills Alca torda and Common Murres Uria aalge – or Common Guillemot as they are referred to in the UK. The Royal Society for the Protection of Birds (RSPB) runs a seabird center along the cliffs of the island where volunteers and staff regularly survey the breeding colonies and answer visitors’ questions. The resident naturalist shared with us the latest numbers: they estimate 100,000 Common Murres to breed on the cliffs, with them 20,000 Razorbills and some 700 pairs of Atlantic Puffins, everyone’s favorite due to their colorful breeding plumage.

Two Atlantic Puffins on Eastern Egg Rock

Atlantic Puffin on Eastern Egg Rock

On the US side of the Atlantic, in Maine, some 550 breeding pairs of these colorful seabirds have been reported in the largest colony on Seal island, ME.

Enjoy some photos of the Irish coastal scenery – I wish my photos conveyed the noise and smell that comes with large seabird colonies like these … David Attenborough in his Life of Birds series refers to these breeding conditions as the” slums in the bird world”.

This slideshow requires JavaScript.

Most of these seabirds are not known for their vocalizations (although Black Guillemots may be exceptional with their distinct whistle; you can hear some in the background of the puffin recording below). Here are some recordings that I found in our collection:

Doug Nelson recorded this Atlantic Puffin on Matinicus Rock, Knox county, Maine, USA on 3 June 1981 (BLB23883):

Lang Elliott recorded a Common Murre on water near the Gaspesie Provincial Park, Bonaventure Island, Quebec, Canada on 1 July 1989 (BLB17181):

Common Eider is another bird that breeds on both sides of the Atlantic. Hear some nestling calls recorded by Don Borror on Eastern Egg Rock, Muscongus Bay, Knox county, Maine, USA on 23 June 1958 (BLB3508):

As you can see, most of these recordings were made a long time ago; time to go back and get some more recent recordings!

About the Author: Angelika Nelson is the curator of the Borror Laboratory of Bioacoustics and team-teaches at the Audubon summer camp on Hog Island, ME.