The Borror Laboratory of Bioacoustics: a non-traditional museum collection

 

It is common for natural history museums to house collections of plants, insects and other groups of animals. The Borror Laboratory of Bioacoustics (BLB hereafter) is a collection of animal sound recordings, one of only about 10 collections of animal sound recordings in the world. We preserve the behavior of an animal making sounds, rather than the animal itself. Why would a biodiversity museum contain a collection of animal sound recordings?

The BLB is named after Dr. Donald Borror (1907-1988), a professor of entomology and zoology at Ohio State who early on realized the biological significance of recording the sounds of insects and birds. About 15,000 of the 45,000 recordings in the BLB were made by Borror himself. Donald Borror was a systematic entomologist, a scientist who studies the evolutionary relationships of insects, and was trained in the museum methods involved in maintaining a “traditional” collection of physical specimens (see previous posts on this blog). Upon leaving the Navy after WWII, he was among the first biologists to use a tape recorder and a sound spectrograph (a machine for making “voice prints”). These tools enabled Borror and his students to record and describe the sounds of insects and birds.

Dr Donald Borror recording bird sounds with a sound parabola

Dr Donald Borror recording bird sounds with a sound parabola

To return to our original question: what is it about animal sounds that is important and merits their collection and archival storage? One of the primary tasks that museum scientists face is describing species. All of our estimates of earth’s biodiversity and much work in all of biology hinges upon being able to demarcate species differences. Traditionally, scientists relied on using anatomical characters that they could see to describe different species. In the 1960’s a common definition was adopted that defines a species as a group of individuals that can breed with one another. This definition recognized behavior as being important in drawing species boundaries. Why? Animals generally don’t mate at random; although there are exceptions, females typically are choosy and males advertise to attract females. Females prefer to mate with males of their own species (because hybrids are usually at a disadvantage), and frequently rely on sound signals to make their choice. This selective pairing leads, over time, to the accumulation of genetic differences between species.

Male birds, frogs and toads, some mammals and many insects use sound signals to attract females. In the 1950’s and 1960’s as sound recording in nature became practical, scientists documented many cases where what was thought to be one species was actually composed of two or more groups that produced different sounds and did not interbreed; that is, the groups met the definition of being different species. For example, after the first decade of sound recording and study, the number of recognized species of crickets in eastern North American more than doubled, as scientists, among them Borror and his students, described song differences. Many similar examples have accumulated in birds also, especially in the 5,000 or so species of song birds.

Of course, every bird watcher knows that a good way to recognize many species is by their song. But the scientific basis for this common knowledge derives from the recordings deposited in sound archives such as the BLB. In addition to being crucial in identifying species, animal sounds are also used to arrange species into higher categories (genera, families, etc.) and also play a role in the study of animal behavior. Many if not most songs of song birds vary geographically and over time. Collections like the BLB contain a rich array of recordings going back to 1948 allowing us to study how sounds vary between species and over time.

About the Author: Dr. Doug Nelson is Director of the Borror Laboratory of Bioacoustics.

 

Fish Face

 

Although any individual fish might be hard to pick out of its school photo,  fish faces can be  remarkably distinct.

 

About the Authors: This blog post is a collaboration between Dr. Meg Daly, Director of the Fish Division & Marc Kibbey, Associate Curator of the Fish Division.  All photos by Marc Kibbey.

 

Your yellow bowl is our YPT

 

Collecting insects is one of the many activities of staff and volunteers at the Triplehorn Insect Collection. Each time we go out in the field and collect we create a tiny snapshot of the insect fauna of that specific place and date.  It’s far from complete, but adds to our knowledge nonetheless. We do not need to go far to find insects that no one has ever studied before. Even in our own backyard, next door to the Museum of Biological Diversity, we find new or rare insect species and discover new facts about known species.

One of the methods we frequently use to collect small flying insects is the pan trap – a bowl with water and a drop of clear, unscented liquid soap.  The soap breaks the surface tension of the water and makes the insects sink.  The color yellow (bright yellow!) attracts many insects, including the parasitic wasps that several of us in the collection study.  Our yellow pan traps, (or YPTs for short) are simple plastic party bowls.  For best results we leave the YPTs out in the field for about 24 hours.  After that we remove the catch, and start the cycle again: fill the YPTs with water, add soap, leave for 24 hours, remove catch. We usually set up 25-50 YPTs in one spot and that’s one sample.

There are a couple of variations on how to empty the traps: scooping the specimens with a fine fish net, or pouring the content of the trap through the net. Either way the specimens get separated from the soapy water, and then are carefully washed with clean water to remove all the soap residue. Once washed, the specimens are preserved in 95% ethanol and placed in a freezer.  That slows the degradation of their DNA and allows for molecular level studies.  Later, we sort the specimens into groups (beetles, wasps, leafhoppers, etc.) and start the long process of specimen preparation for study.  The YPTs are washed and saved for the next collecting season.

Click or tap on the image to enlarge.

 

A heartfelt thanks to the people in these photos: Zach Hurley (collecting, adding soap, adding water, washing, sorting), Matt Elder (collecting), Norman Johnson (checking the catch, emptying YPT), Hans Clebsch (adding water to YPTs); and to the anonymous biker going by the Museum building.

 

About the Author: Dr. Luciana Musetti is the Curator of the Triplehorn Insect Collection at Ohio State University. All photos are courtesy of the author, except for the one of Hans Clebsch.

 

You’re an insect curator. Cool! So what is it you do?!

 

We frequently give tours of the Triplehorn Insect Collection to school groups, families, etc.  Since most entomologists like to talk about their insects, that’s usually a fun time for me.  It is also a great time to flex my General Entomology muscles.  Visitors ask lots of questions, some of them interesting (How many ants are there in an ant’s nest? Do young cicadas sing underground?), some funny (Do you eat bugs every day?), some actually very difficult to answer (How many bugs are there in the world right now, how much do they weigh, and how do you know? How come you don’t have a list of all insect species in the world?).

Open collection cabinet showing insect drawers.

Open collection cabinet showing insect drawers.

During a recent tour of the collection, after my brief intro on the history and structure of the collection, an 8-year old visitor asked me point blank: ‘If all the bugs in the collection are dead & put away in their little boxes, what do you do the whole day?’  Somebody behind me gasped, but I thought that was a good question, especially as I had just told them that we keep our specimens in cabinets, safe from humidity, light, and especially other bugs that might want to try and eat the dead specimens. So I told them that, yes, we keep the insects safe in cabinets, but that’s when they are not being used. And use them we do, a lot!

Much of what we know about the natural world comes from museum specimens. Scientists use the specimens and the data associated with them to answer many basic questions such as:

  • Where can you find this (species of) wasp? – museum specimens have labels attached to them that contain locality information.  The geographic coordinates for the locality can be plotted on a map like the one below. Data for multiple specimens of a species help us understand the geographic distribution of the species.

    Distribution of Pelecinus polyturator based on museum specimen data.

    Specimen records plotted on a map show the skewed distribution of Pelecinus polyturator, a parasitoid wasp, in North America.

  • When is the best time of the year to find that wasp? – specimen labels may contain a date of collection, which then may help pin-point the time of the year the species can be found in a specific place.
A detailed specimen label.

This label provides both detailed locality data and biological information (host species) as well.

Detailed specimen labels.

Label including geographic coordinates, altitude, type of trap, and habitat.

With locality and date of collection alone we can already learn a tremendous amount about that species of wasp.  For some areas, we can look up weather reports from that exact day and see if it was raining that day, what the average, the maximum and minimum temperatures were, also the barometric pressure, and other environmental factors that may (or may not) affect the species.

Labels may provide information on the way the specimen was collected (examples: by hand at light; using traps like a Malaise (below, middle), or yellow pans (below, right)), and the kind of vegetation (forest, grassland, prairie, etc.) encountered in the area it was collected.

Light trap

Malaise trapYellow pan trap

 

 

 

 

Sometimes labels also include information on what the specimen was feeding on, burrowing in, coming out of, what other species it was associated with, and more. It is quite amazing how much valuable information insect collectors manage to squeeze onto a tiny piece of paper!

The label information found on museum specimens is extremely valuable data for scientists trying to learn about a species and to start assessing the impact of environmental changes on living organisms.

Now, back to the young visitor’s question: ‘What do we do the whole day?’ One of the major responsibilities of a curator (= caretaker) is to make specimens and specimen data available for scientific study. That can be done either by carefully packaging and sending the specimens on loan to a scientist, or, more recently, by databasing the specimen information and making it available online to the scientific community and the general public.  Either way, that involves a lot of work, particularly in a large — we hold about 4 million dry specimens — and, relatively old — we just turned 80 in 2014 — collection like the Triplehorn.  It is not uncommon for us to loan 3,000 specimens to one scientist. The largest loan we sent out to date contained 28,000 specimens – we worked on the preparation of that loan for months!  We also welcome scientists who want to come on research visits to the collection.

So, just making the specimens and the specimen data available to the scientists is a lot of work. We could stop right there and we would still be very busy every day of the week. But we don’t stop there, oh no!  The collection keeps growing in various ways.

  • Scientists deposit voucher specimens of their research with us — that’s actually one of our main missions, to house and preserve vouchers of scientific studies so other scientists can examine those specimens if and when they need to.
  • Private insect collectors also donate their collections to us — just last month we were presented with the late Steve Sommer Collection of butterflies and moths from Ohio and the Midwest, about 1,000 specimens.
Repairing specimens.

Repairing specimens.

These new arrivals are placed in a -40°C freezer for several days to kill any potential pests that might be infesting the specimens.  Next they are examined for damage, and even sometimes fixed — broken parts are glued to a card or put away into tiny vials or gel caps. After this basic upkeep work is done, we add the specimen data into our database — sounds simple, but there are many steps to that operation, and, you guessed, a lot of work involved. Finally, we add the specimens to the main collection.

I won’t get into details of the curatorial or the databasing work here, but in case you are interested, you can read about it in the collection’s blog, the Pinning Block, and follow our  posts on our Facebook page.

Oh, and did I mention we collect?  Yes, we collect new specimens for our own research (in my case, and Dr. Johnson’s, it is parasitoid wasps), or to fill in the gaps we have in the collection. That’s a big source of growth and (guessed righ again?) more work!

Dr. Norman Johnson collecting parasitoid wasps in South Africa.

Dr. Norman Johnson, Director of the Triplehorn Insect Collection, collecting parasitoid wasps in South Africa.

Newly collected specimens are always being prepared, dried, mounted, labeled, databased, and added to the collection.  These specimens will one day be studied by scientists and maybe even be described into a new species.  In the meantime it is up to the curatorial staff of the collection to keep them safe and accessible. And that’s an entirely new post. Keep tuned!

About the Author: Dr. Luciana Musetti is the Curator of the Triplehorn Insect Collection at Ohio State University. All photos are courtesy of the author.

Thanks to Norman Johnson & Gisele de Souza da Silva for careful review and thoughtful suggestions.