Stefan Hill, sorter of tissues

Sorting and documenting tissue samples.

Sorting and documenting tissue samples.

One of my main projects during my internship at Texas A&M University’s Biodiversity Research and Teaching Collections (BRTC) was sorting through and organizing a collection of tissue samples from past research by Dr. Ira Greenbaum. These tissue samples were primarily harvested from a variety of Peromyscus species over decades of research. Totaling over 7,000 combined liver, heart, kidney, and testicle samples, the collection had been stored inside freezers in Dr. Greenbaum’s lab for some time, until those freezers started to fail.  Luckily the BRTC was able to take in these tissue samples and continue to preserve them by placing them within the Genetic Resources collection.   Notably, the skins and skulls from which these tissue samples were taken are already included within the Mammal Collection. Therefore, obtaining these tissue samples greatly benefits the collections overall as now we have all samples associated with each specimen. As one can imagine, sorting through all these frozen tissues is a huge and somewhat numbing (literally) task. Fortunately for the staff at the BRTC, there is an army of undergraduate interns such as myself that will work on such projects.  The task may have been simplistic in itself, but it gave me some insight to the efforts that are required at times during real scientific research.

Organizing the Greenbaum tissue collection involved taking the tissue samples out of the original cardboard storage boxes, placing them into new plastic vial storage containers, and recording their information into an excel tissue spreadsheet where they could be easily located. These new containers were organized into a 9 x 9 grid system capable of holding up to 81 individual vials; columns were labeled A through I and rows labeled 1 through 9. Each new container was numbered and entered into the tissue excel file on an individual spreadsheet that had the empty cell slots organized A1-I9 ready for vial placement.   Written on the side of every vial contained the initials of the researcher, followed by that collector’s collector number and a letter designating its tissue type.  This information would be recorded into the spreadsheet alongside the cell number giving each tissues’ specific location.    After organizing all the tissues from the storage into new containers, the next step was to cross reference the organized vials’ collection ID with another excel spreadsheet from the Mammal Database that contained the specific information about each individual specimen from which the tissue came from.  The purpose of this cross-listing was to record that a specimen cataloged in the Mammal Collection did indeed have a tissue and note the tissue location (box and cell slot). Although time consuming, the overall process was fairly straightforward and once I got into the rhythm of creating new excel sheets for each tissue box, reading the tissue information, and entering it into the excel file, I was able to fly through the process. My knowledge of the Excel program definitely increased as I discovered faster keyboard shortcuts to enter the data at a much more efficient rate. It wasn’t exciting work but by listening to music, TED Talks lectures, and audiobooks, I was able to stay focused and relaxed enough that time went by much faster. The biggest challenges and frustrations involved with this project was merely trying to decipher some of the written information on the vials. A combination of illegible hand writing and non-permanent ink made reading a fair number of tubes almost impossible.  I would either have to look for patterns in the numbering system of how they were originally sorted to deduce what was written or simply record UNREADABLE in the Excel file.

After accumulating several dozen hours doing this project, I often wondered what the overall purpose of this project was. Then about halfway through the semester, I happened to stumble upon a magazine article highlighting the importance of biodiversity collection museums. The author pointed out that they play an important role by tying together a number of scientific fields including genetics, population studies, migration patterns, evolutionary history, and taxonomy that can be used to further benefit the goal of conservation. These tissue samples that I had been sorting were a contribution to that direct effort.  They can be used by future researchers for generations to come for a variety of studies to further advance the field of biodiversity.

Small mammal preparation at the BRTC

Noel Lyon – BRTC intern

One of the more hands on tasks at the Biodiversity Research and Teaching Collections (BRTC) is to prepare scientific specimens to be cataloged into the mammal database. Scientifically prepared skins held in natural history collections provide morphological and physical characteristics of individuals and the species as a whole. These data can illustrate how individuals and a species can vary through time and geography, creating a snapshot of a species in a given time and location. Furthermore, additional data such as the life stage, tissues, and parasites gathered during the collection of a particular specimen can also provide researchers with useful data.

Baiomys taylori specimen prior to processing.

Baiomys taylori specimen prior to processing.

During my internship, I prepared several specimens in the order Rodentia. I did not have trouble skinning after receiving excellent instructions provided by Dr. Light. But stuffing specimens proved to be a challenge. Skinning of all mammals follows a general procedure that can be altered depending on the desired outcome (pelt, museum specimen, meat).  A cut is made up the ventral side of the body from just above the urogenital area to about the forelimbs. This allows room for the skin to be worked off the limbs and body using a counter pull system. This system involves pulling the body one way while simultaneously pulling the skin in the opposite direction. Extra care is taken around the limbs and tail to prevent the skin from tearing. Similarly, the face needs to be worked off of the skull very carefully to ensure that the nose, ears, and eyes remain intact. The bones that comprise the digits and feet on the right side of the animal, as well as the baculum for males, are kept in the skin to maximize the amount of information that the specimen provides.

Wire is traditionally placed in the tail and limbs to ensure that these portions of the specimen are laid out straight. Small specimens such as mice require very thin wire, which unfortunately is easily bent. I found inserting the wire into the right forelimb and hindlimb to be the most difficult and sometimes frustrating part of preparing a specimen. Wire is inserted in the feet so that it sits between the bones and the skin. There is very little room in this area, and inserting the wire requires gentle poking and manipulation to slide into place. Cotton is often wrapped around the section of wire that sits in the area of the legs vacated by the femur and tibia in the hindlimb, or the humerus, radius and ulna in the forelimb. This is done to give the prepared skin as much of a lifelike appearance as possible.

Cotton is also wrapped around the wire used in the tail. The process of inserting the wire into the tail is much easier than in the limbs. However, the cotton must be wrapped very tightly around the wire or it will slip and bunch up which makes insertion impossible. Additionally, the thickness of the cotton must taper towards the tip of the tail, with it being widest at the base of the tail.

Scientifically prepared Baiomys taylori ready for drying, fumigation, and installation into the mammal collection.

Scientifically prepared Baiomys taylori ready for drying, fumigation, and installation into the mammal collection.

Cotton is also used to stuff the body cavity and head of the animal. Cotton has to be placed just right in the nasal region of the animal, otherwise it looks very odd; for rodents, you want the specimen to have a pointy nose just like in life. I found the aid of forceps crucial in this step. After estimating the amount of cotton needed and cutting it into the shape of a triangle, I would fold up one corner very tightly and grasp it with the forceps. After carefully placing this end into the tip of the animals nose, I would release the forceps and the cotton would expand and fill in the nose. After that, I would fold the rest of the cotton into the body and sew up the incisions made during skinning. This step often took the longest, as removing and manipulating the cotton was necessary to ensure that body proportions were more or less realistic, and dorsal and ventral surfaces were smooth. The final step is to pin the specimen to a piece of foam to dry. This step requires an artistic touch to make the animal appear as lifelike as possible. The nose, head, and tail are lined up while the legs are stretched out pointing directly to the front and rear of the animal. Lastly, brushing the fur and minor tweaking can make a huge difference in appearance.

With biodiversity declining around the world, properly prepared and cared for specimens are becoming increasingly valuable. As species become scarce, studying them becomes more difficult. Natural-history collections provide samples of species that may otherwise be unobtainable. Data gathered from prepared skins may provide insight into why a species is in decline in the wild, as well as how individuals vary over time and space.

Stefan Hill, Dermestid Care Level: Expert

Skeletonized specimen being removed from the Dermestid beetle colony.

Skeletonized specimen being removed from the Dermestid beetle colony.

My name is Stefan Hill and during my final semester as an undergraduate at Texas A&M University, I had the fortunate pleasure of interning at Texas A&M University’s Biodiversity Research and Teaching Collections (BRTC).   It was the busiest semester I have had to date in my entire college career, but the experience I gained as an intern in these short few months have been one of the highlights of my academic study.  I learned the ins and outs of how the specimens in the collection are selected, prepared, and managed for long term storage to promote the process of biodiversity conservation.  One of these processes that I was directly involved with included the care of the dermestid beetle colonies used to clean animal skeletons.  These beetles will eat the flesh off a skeleton and after a few days of chowing down, will leave a perfectly intact skeleton.  It was pretty fascinating to observe this process first hand.  I was able to witness all kinds of animals being placed into these colonies and, after only a matter of days, coming out looking completely unrecognizable.  From watching deer, bear, and alligator heads to whole shark and squirrel bodies being consumed was a pretty cool experience overall.

The procedure of specimen preparation that I was involved in went in this sequence: Specimens would be skinned and tagged and placed in a freezer until there was room for them in the beetle colony.   A metal tag with an ID number was then matched with the specimen number as a secondary means to keep track of each individual specimen.  This is especially important because the beetles tend to move everything around and the skeleton becomes dismantled while the bugs are feeding. Once removed from the bugs, the skeletons are soaked in a 3:1 ratio of water to ammonia hydroxide to further clean the bones of oils and organic matter for 12 hours.   If left to soak any longer, the chemical can actually do damage to the bones so it is crucial to remove them within this time frame.  From the beginning I was warned that ammonia hydroxide is a very strong irritant and is incredibly volatile.   Therefore, when using ammonia lots of ventilation as well as eye protection is needed, otherwise your throat, nose, and eyes will become horribly agitated by the fumes.  Once removed from the chemical solution, the skeletons are air dried for 24-48 hours, boxed up, and placed into the freezer for another 7-10 days for a final fumigation step.  After freezing, the specimen is assigned an identification number and installed into the collection for final storage.

The only real downside working with the beetles was the smell.  The colonies were located in a separate shed several hundred feet behind the BRTC building for good reason.  These things stank like no one’s business.   The decaying carcasses combined with the beetle excrement and substrate creates a very strong, pungent, unique smell.   It’s not necessarily a smell that makes you gag or get sick, but it’s still not all that pleasant to work with for long periods of time – mainly because it sticks to your clothes and is very noticeable to anyone else afterwards.   I learned that lesson pretty early on after working with the beetles one afternoon and then biked back to campus on a particularly hot day for my next class.   Sitting through a 50 minute lecture radiating a funky, mutated B.O. while my classmates conspicuously wrinkled their noses was enough ostracism for me to start bringing a change of clothes any time I worked with the beetles.

Mammal Collection at the BRTC – from the eyes of an intern

Noel Lyon – Spring intern 2015

The mammal collection at the Biodiversity Research and Teaching Collections (BRTC) contains thousands of scientific specimens. These include alcohol specimens, skeletons, skulls, and scientifically prepared specimens. One of the greatest dangers to skeletons, skulls, and alcohol specimens is being dropped, whereas scientifically prepared specimens are threatened by insect pests. One of the many insect pests detrimental to preserved animal skins is the cigarette beetle. Larvae feed by burrowing into the skin, which can damage or ruin a museum specimen. Feeding by adults on the proteins within the skins can also ruin specimens. Adults are small, about 2-3 mm in size, and are reddish brown in color. The eggs of cigarette beetles are coated with a layer of B vitamins when they pass through the oviduct upon laying, which larvae can utilize as a food source (Cabrera 2001). Females lay 10-100 eggs in the food source and larvae typically emerge in 6-10 days (Cabrera 2001). The life cycle of the cigarette beetle ranges from 40 to 90 days depending on temperature and availability of food (Cabrera 2001). With the large number of eggs produced by each female in addition to their relatively long life cycle, an unchecked infestation of cigarette beetles has the potential to destroy many valuable museum specimens and the data they provide.

Mammal Range1

The mammal collection at the BRTC

An important, although seemingly dreaded task, is to thoroughly search every case in the collection for signs of a cigarette beetle infestation. I spent a good deal of time inspecting hundreds, if not thousands of specimens for signs of beetles. Opening drawers and looking for beetles simply isn’t sufficient. Every specimen must be removed and checked. The average case holds about 10-15 drawers, and depending on the size of the animals, one drawer can hold up to 30-40 specimens. If I found a live beetle, then the case was fumigated using ethyl acetate to kill the beetles and remove the infestation. Whenever I came across the body of a dead beetle, I pinched it between two fingers to estimate its age. If the beetle was juicy, than it was relatively fresh, and every specimen was examined extremely carefully to determine if there was an active infestation. If an infestation was found, the case was fumigated. If the beetle crumbled to dust when I pinched it, than it was old, and the bug and specimen debris was vacuumed out. In addition to looking for signs of insect damage, I also replaced or added mothballs to the jar lids that are in every case to deter cigarette beetles and other insect pests. Lastly, I also recorded my findings on a log kept inside each case to monitor infestations over time. Thankfully, I did not find any infestations.

Mammal Range2

Typical drawer of specimens in the order Rodentia.

A great deal of information is contained with each specimen housed within the BRTC. For mammal specimens, this information includes collector and collector number, the location they were collected, any measurements taken at the time of collection, and sometimes other tidbits such as the cause of death and whether the animal was reproductive. This information is included in the database and on tags associated with each specimen. However, these specimens and their information lose their value if the specimens are eaten or destroyed by cigarette beetles. As I went through the drawers and cases, I read the information contained on many of these tags, and I was amazed at the age of some specimens. Some are from the 1920’s and 30’s and are in excellent condition. This would not be possible if not for vigilance by many people looking for cigarette beetle infestation signs over time. I was not the first, nor will I be the last person to check the cases. I can’t say it was the most exciting thing I’ve ever done, but I did learn a lot more than I thought I would.

Literature Cited

Cabrera, B.J. 2001. Cigarette beetle. Entomology and Nematology. University of Florida.



Libraries of Life –

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Excellent article from NY Times about collections!

Libraries of Life –

Museums: The endangered dead : Nature News & Comment

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Museums: The endangered dead : Nature News & Comment.

Getting the Bats in Order

Another bit from our WFSC undergraduate intern Lauren Wimbish, this time she’s in our collection of bats organizing their skins and skulls-


Lauren Wimbish proofing the order of bat specimens in the collection.

This past June I spent many hours reorganizing the bat collection at the BRTC. Bats are mammals that belong to the Order Chiroptera, which is the second largest mammal group (only rodents belong to a more diverse Order). They are also the only mammals that are capable of sustaining true flight. The collection consists of many different species of bats from all over the world, but mostly the specimens are from the Americas. Reorganizing each case consisted of going through each drawer and making sure the specimens were in alphabetical order by family, genus, species, and geographic locality. Each drawer would contain at least one family of bats. The bats within that family were alphabetically placed by species name and geographic region within that same species. Usually, each case had about 12-15 drawers and would take roughly an hour to go through. Most of the specimens I organized were fairly small and did not vary much in size. While shuffling through the bats I would always put my headphones in and enjoy some music to help give a relaxing work setting.  On days when the air conditioning was struggling to cool the building this was especially necessary. Texas summers can be pretty brutal, even inside. On a few occasions my work lead me outside and I would have to tough it out in the Texas heat.

Intern Lauren Wimbish

Lauren with Jars

Checking the fluid preserved mammal specimens.

Hi! My name is Lauren Wimbish and I am a Wildlife and Fisheries Science major at Texas A&M University. Part of my experience here at Texas A&M is having an internship. This past summer I worked as an intern at the Biodiversity Research and Teaching Collections (BRTC). Although I have had multiple classes at the BRTC, such as Natural History of Vertebrates, Mammalogy and currently Ornithology, this past May was my first time working within the collections. For a good chunk of May and June, I spent a fair amount of time working in the mammal alcohol collection. These are fully intact specimens that are put into jars filled with alcohol to preserve them. The mammal collection has about 12,000 specimens preserved in alcohol and when I began my journey of organizing them I started on rodents. I primarily worked with different species of rats and mice and occasionally a gopher. There also are many other mammals in the collections besides rodents, such as bats, felines, and my favorite: a Pronghorn Antelope. My main task working in the mammal alcohol collection was to assess what was in each jar. I would get a jar and take out each specimen; some jars would have one or two specimens while others would have 20 or 30. I would take every specimen out of the jar and then essentially check to make sure it is where our records say it should be. If anything was off/missing, I would make a note for the curator so corrections could be made later.  The work was generally quiet and slow. So most days when I would come in I would put in my headphones and listen to some music while I would go into my own little place for a few hours. The cool part of doing this was getting to see all the little differences in the species.  Some of them have had large amounts of tissue samples taken from them, so not every specimen was perfect per se. Some of the internal organs were exposed in these not-so-perfect specimens. One of the coolest things I recall was being able to see the fetal offspring in some of the female rats. Not every day was as exciting as when I saw the fetal rats.  On days that were moving a little slow I would mix things up by working with the collection of bats we store in cases.

BRTC specimens used in seahorse study

Recent publication from colleagues in Brazil identifies 3 species of seahorses in Brazil.

The BRTC contributed radiography of specimens to help with the morphological component of the study.

Radiographs of BRTC specimens used in this study.

Radiographs of BRTC specimens used in this study.

River barriers and cryptic biodiversity in an evolutionary museum

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New publication from Curator’s Voelker and Light of the BRTC!

River barriers and cryptic biodiversity in an evolutionary museum – Voelker – 2013 – Ecology and Evolution – Wiley Online Library.