Friday, January 22, 2016

Eatlemania Hits the Airwaves!

We are so excited to announce that you can now watch The Eatles munching the night away in real time at the Organ Laboratory YouTube Channel.

Immediately you will notice three "dishes" they are feasting on (from closest to farthest from camera):

1) Thanksgiving turkey (Meleagris gallopavo) remains from my mother in law's kitchen! In our family, thanksgiving is a time for sharing with family and friends and beetles. In keeping with the outreach spirit, our colleague at IU School of Medicine, Dr. Bill Sullivan, recently wrote about some interesting turkey facts at The 'Scope. Enjoy.

Winner Winner Turkey Dinner
2) "St. Louis style" spare pork (Sus scrofa) ribs from City BBQ. As a big fan of barbecue, I was surprised to learn that "St. Louis style" ribs has nothing to do with being coated in sticky barbecue sauce, and everything to do with the actual cut of meat. "St. Louis style" ribs are the spare ribs and are usually meatier and have higher fat content that baby back ribs (or loin ribs). The more you know...


I want my baby back, baby back, baby back spare ribs.

3) Amber the hedgehog, who is slowly but surely being cleaned for us by The Eatles.


We hope you enjoy watching!

Contributed by: Jason Organ, PhD  

Sunday, January 17, 2016

Little Brown Bat

Myotis lucifugus. Photo from Animal Diversity Web
Over the last week, the Eatles have completely devoured the soft tissue remains of a little brown bat (Myotis lucifugus), with a great big story. Well, maybe neither "big" nor "great"... but certainly a "good" story. In Summer 2010 we attended the birthday party of a family friend's toddler. The party was thrown at the birthday boy's grandparents' farm located in Sullivan, Missouri, about 65 miles SW of St. Louis.

As a comparative anatomist by training, I have been fortunate to learn so much intricate, detailed anatomy through dissection. However, with that fortune sometimes has come the misfortune of using specimens that were less than fresh - ripe, even. When we arrived at the birthday, I noticed the very faint, but unmistakable, stench of decomposition wafting from under the picnic table where the birthday cake was set. I looked under the table and found a recently deceased little brown bat. I discreetly informed the party host of my find, and as any self-respecting comparative anatomist would do, I asked if I could take it home! So my friend the little brown bat from Sullivan stayed in my lab chest freezer for the next five and a half years awaiting his fate at the hands of The Eatles.

Bats belong to the mammalian order Chiroptera, which is the second most speciose group of mammals after rodents (Order Rodentia). Chiroptera is divided further into two groups of bats: the mega bats - the large Old World fruit bats; and the micro bats - the small, generally insectivorous bats. The little brown bat belongs to the microchiropteran family Vespertilionidae, which includes over 300 species of common bat.


Little brown bat feast
Bats are fascinating creatures. Most vespertilionids navigate by utilizing a combination of eye sight and echolocation. In order to echolocate, bats create a series of high-pitched sound pulses at frequencies that their sense of hearing is optimized to detect (usually well above the range of human hearing). These sound pulses originate in the animal's larynx (vocal apparatus) and resonate through the nose and mouth. The sound pulses reflect off of objects in the distance, and the echo that returns indicates how far away the object is, such as food or trees or another bat. These echoes can also help the animal determine how large the object is, and whether or not it is moving, which is helpful for finding potential mates and prey, and for avoiding predators. You can read more about echolocation in bats at the Bat Conservation Trust.

Little brown bats are small in size, averaging somewhere between 5 and 14 g in weight and between 60 and 100 mm in length (head to tail), with a wingspan that is 222 to 269 mm. They live all over North America except in the forested high mountains of Mexico, and their diets consist largely of insects such as moths, wasps, beetles (oh no... please NOT BEETLES!), mosquitos and mayflies. Unlike many bats, little brown bats do not migrate long distances to warmer climates during the winter. Instead, they move their roost sites to places where outside temperatures can be modulated in colder temperatures, such as inside abandoned mine shafts or caves, usually within 100 miles of their summer roosting sites.


Upper Limb Skeletal Homology, Arizona State University.
But probably the most fascinating thing about bats is that they are the only living mammals that have evolved anatomical adaptations for sustained flight. The basic elements of the mammalian upper limb musculoskeletal system are present in bats, although they have been significantly modified to support a wing membrane (patagium), and the sizes of many of the bones and muscles differ from those of nonflying animals. For example, the distal elements of the upper limb - the metacarapal bones of the hand and the phalanges of the fingers - have been elongated in order to provide support for the patagium and to control its movements. The patagium, which is a double-layered membrane of skin derived from the abdomen, encloses a series of nerves, blood vessels, and muscles, and it extends from a bat's fingers to the torso and abdomen and to the lower limb. In order to support the patagium with the lower limb, a bat's hip joint is rotated 90° so the knee faces backward. This altered hip joint prevents normal walking in bats, but also allows the bat to hang upside down in its roost. Upside down hanging is also helped by a tendon configuration in the toes that locks their toes in place so they can continue to hang without conscious effort during sleeping.
 
Contributed by: Jason Organ, PhD 

Read more about bat science in these references:

Dzal YA, & Brigham RM (2013). The tradeoff between torpor use and reproduction in little brown bats (Myotis lucifugus). Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology, 183 (2), 279-88 PMID: 22972361 

Fenton, M., & Barclay, R. (1980). Myotis lucifugus Mammalian Species (142) DOI: 10.2307/3503792

Veselka, N., McGuire, L., Dzal, Y., Hooton, L., & Fenton, M. (2013). Spatial variation in the echolocation calls of the little brown bat ( ) Canadian Journal of Zoology, 91 (11), 795-801 DOI: 10.1139/cjz-2013-0094

Wednesday, January 13, 2016

African Pygmy Hedgehog (Four-Toed Hedgehog)

From 2008-2012 our lab was located at the Saint Louis University School of Medicine. We spent four years there studying the comparative anatomy of primates before venturing into our biomedical research areas when we moved to Indiana University. During our time in St. Louis, we established a collaboration with Jenny Joyce, the Elephant Manager at Grant's Farm. Grant's Farm is the 281-acre ancestral home of the Busch family (of Anheuser-Busch fame) and is named after Ulysses S. Grant, the 18th President of the United States, who had previously worked a portion of the land. Today, Grant's Farm is a well regarded wildlife park dedicated to education and public outreach about the 900 different species that call the park home. Our collaboration with Jenny allowed us to obtain remains of animals that died of natural causes at the wildlife park, and we are greatly appreciative.

One of the animals that came to us from Grant's Farm was an African pygmy hedgehog (Atelerix albiventris) named Amber. Given the association with Anheuser-Busch, it should come as no surprise to beer connoisseurs that Amber had a brother named Bock.


Photo from University of Michigan's Animal Diversity Web (animaldiversity.org)
African pygmy hedgehogs are members of the mammalian Order Insectivora, which includes hedgehogs, moles, tenrecs, golden moles, solenodons, and shrews, divided among six families (African pygmy hedgehogs belong to the family Erinaceidae). They are generally solitary animals that range in Southern Africa from Senegal to Sudan to Zambia, and live in deserts and scrub forests. They feed mostly on insects and spiders, and for a long time were brought out of Africa by pet traders - this is no longer legal, however. One of the most distinctive aspects of this animal is the presence of sharp quills covering its back and sides. These quills are present at birth but covered in a membrane that prevents them from injuring the mother during delivery. When a hedgehog is threatened by a predator it has the ability to roll itself into a tight ball, which forces its quills to splay in all directions and protects the animal from being eaten.

The Eatles have been feasting on the remains of Amber for the last several days, and they are making quick work of cleaning her skeleton. Below is a picture from this morning. I will post additional pictures as they progress, and of course will be sure to post a picture of the final product.









Contributed by: Jason Organ, PhD 

Read more about African Pygmy Hedgehogs:

Nichols, J. 1999. "Atelerix albiventris" (On-line), Animal Diversity Web. Accessed January 13, 2016 at http://animaldiversity.org/accounts/Atelerix_albiventris/

Girgiri I, Olopade JO, & Yahaya A (2015). Morphometrics of foramen magnum in African four-toed hedgehog (Atelerix albiventris). Folia morphologica, 74 (2), 188-91 PMID: 26050805 

Girgiri, B., Ibrahim, B., & Bwala, A. (2015). Morphometric studies of some visceral organs and gastrointestinal tract of four-toed african hedgehog (atelerix albiventris) Journal of Morphological Sciences, 32 (1), 29-32 DOI: 10.4322/jms.071014