Friday, November 30, 2012

Burying Beetles

    Earlier this fall we got a donation of American Burying Beetles (Nicrophorus americanus) to safeguard in our collection, the specimens of which were part of a survey project done by one of our museum's curators, Dr. Gary Schnell. He, along with students, did surveys of the endangered beetles in Arkansas and Oklahoma to study what habitats they prefer, and to learn more about their biology. Dr. Schnell had been working on the project from 1992 to about 2005 surveying the two sites (Fort Chaffee and Fort Gruber, respectively) during several summers in that time frame. The beetles that were found dead in the survey were kept as voucher specimens, and are now part of our collection thanks to the work of our volunteer Sally, who has diligently been pinning and processing them from alcohol.
American Burying Beetles Sally has processed.
   Why are American Burying Beetles so important? Well, the reason is that they are one of the few insects on the Endangered Species list. Its believed that these beetles used to have ranges across the entire Eastern United States, but are now just limited to a few counties in Oklahoma, Arkansas, Kansas and Nebraska.
   These beetles feed on a very specialized diet: carrion (dead animals), which is one of the reasons that its thought they have had such a reduction in their distribution. Dead animals, especially in the right size that the beetles can use, is fairly hard to find. These beetles need animals the size of a dove or chipmunk that they can easily manipulate into a burrow to bury with their eggs. The eggs then feed on the nutrients of the carrion to develop. As land use changes and the availability of small animals decreases, so have the beetles. According to information on Wikipedia.com from the US Forest Service, their life cycle is as follows:

   "During the winter months when temperatures are below 15 °C (60 °F) N. americanus adults bury themselves in the soil to overwinter. When temperatures are above 15 °C (60 °F) they emerge from the soil and begin the mating and reproduction process. Burying beetles are unusual in that both the male and female take part in raising the young. Male burying beetles often locate carcasses first and then attract a mate. Beetles often fight over the carcass, with usually the largest male and female individuals winning. The victors bury the carcass, the pair mates, and the female lays her eggs in an adjacent tunnel. Within a few days, the larvae develop and both parents feed and tend their young, an unusual activity among insects, but a characteristic shared with the. Brood size ranges from one to 30 young, but 12 to 15 is the average size." 

Its this complex behavior, among other things, that makes them so interesting as well as atypical for beetles. Most beetles do not have this type of maternal care (parents taking care of the young); usually beetles lay their eggs and then leave them to fend on their own!
American Burying Beetles are recognized by their orange antennae segments, the orange area on the head and pronotum (shield like structure behind the head), and the orange stripes on the wings.
     Having these beetle specimens in our museum helps keep the record of their existence for future generations. Hopefully the beetles will have a bright future ahead of them with their protected status and captive breeding, but if not we can safeguard their record of being here none the less.

Thursday, November 15, 2012

Mantids!


This is the first inaugural post from Mantidae, our Collection Manager. Thank you Mantidae for posting!

Hello!  This is my first contribution to the Recent Invertebrates blog!  I’m a member of the department but actually a trained Ornithologist (a biologist who studies birds).  Hopefully, I can provide some non-Entomologist perspective to this blog.

My favorite group of insects has always been the praying mantis. The name “Praying Mantis” comes from their typical "prayer-like" posture with folded forelimbs.

European Mantis (Mantis religiosa)
http://en.wikipedia.org/wiki/Mantis_religiosa
  According a Muslim myth, the praying mantis always prays facing Mecca. Mantis is a Greek word for “prophet” and has the reputation of having supernatural power in some cultures.  For example, many Europeans believe that the mantis points lost children home, and in some African cultures, it is thought to raise the dead. 


 
Praying mantises are the most voracious predators in the insect world and will devour any creature they can overwhelm, including small scorpions, lizards, frogs, fish, and even birds and rodents!  In the 17th century, Chinese fighters created a style of Kung Fu (Chinese martial arts) inspired by the praying mantis that can defeat much larger opponents with the split second timing and precision.

 
 
Praying mantises have forelimbs with the jackknife like apparatus, and once they grab their prey, there is no chance of escape for the victim.  Their compound eyes are widely spaced and laterally situated, creating a wide binocular field of vision and, at close range, precise stereoscopic vision.  They can judge the speed and distance of preys by swaying their head side by side, computing perfect timing of attack.

There are over 2,400 species of mantids in the world.  I was a little bit disappointed when I learned that they are the most closely related to termites and cockroaches (Eew!). Who could imagine such beautiful creatures could be related to cockroaches?  You may have only seen brown or green ordinary-looking praying mantises in the backyard or roadside of Oklahoma, but it includes species that are incredibly diverse in size, shape, and color.  Some of them are so well camouflaged in the background, and you may never be able to find them.  Here are some of the good examples:

Giant Dead Leaf Mantis (Deroplatys desiccate)
Orchid Mantis (Hymenopus coronatus)
http://en.wikipedia.org/wiki/Hymenopus_coronatus
Spiny Flower Mantis (Pseudocreobotra wahlbergi)
http://en.wikipedia.org/wiki/Pseudocreobotra_wahlbergi
Ghost Mantis (Phyllocrania paradoxa) http://en.wikipedia.org/wiki/Phyllocrania_paradoxa
 
If you are lucky enough, you may find egg cases of the praying mantis in your backyard in late fall or winter (or you can also buy their egg cases online).  When I was in the first or second grade, I decided to keep a little brown foam-like egg case in the plastic insect case all the winter.  One day in the following spring, I discovered hundreds of small praying mantises started to come out of the egg case.  You can imagine how excited I was!  Although I wanted to stay with the baby mantises, I had to go to school that day. When I came back home in the afternoon, I discovered that the tiny mantises all escaped from the small slits of the insect case, and I couldn’t find even a single one of them anywhere in the house.  So be careful if you decide to experience the wonderful birth of baby mantises!  The following video shows the life cycle (from egg to adult) of preying mantis: 

Aren’t they just fascinating? 

Hiatus

Hi, this is Katrina. This past Friday both myself (Miridae) and Laura (Tardigrade) were at the Entomological Collections Network Meeting and the Entomological Society of America Annual meeting, so we unfortunately could not post a blog article for that day. But, stay tuned for the one this week by our Collection Manager Tamaki about Mantidae, and we will get back on schedule next week!

Friday, November 2, 2012

Hairs!

      As someone who studies bugs for a living, one of the most difficult parts of my job is trying to convince people that the little guys should get as much attention as the big, furry, and feathery guys. There is something innately attractive to humans because fur reminds us of our own mammal ties: one of the unifying characters of being a mammal is having hairs or fur, among other things. So when we see fur, fluff, or hairs we feel a slight sense of kinship.  
Awwww!....fluffy, sleepy kitty and fellow mammal
       Well, bugs don't really have "hair" or "fur", which sets them in a slight disadvantage in that respect. Words that come to mind with bugs are "slimy", "squishy", and "gross". However, many insects have setae, which are like hairs, but since insects come from a different ancestor than mammals its actually something different. The function of the setae is also different.
Awwww?!?...fluffy-legged Clearwing moth...not mammal
        For insects, setae are often used to sense their environment around them. If a setae is bent a certain direction by a puff of air, it triggers nerves in the exoskeleton to let it know there is wind. Because insects have a hard exoskeleton rather than skin, its less sensitive to mechanical (physical) stimulation unless there is something like setae to interact with the environment. Even the hardest-shelled beetles with tough, smooth exoskeletons have setae around the joints between segments to "sense" where the other segments are and how they are moving. 
Rhinoceros beetle. If you look at the bottom of its top "horn" you'll see an example of setae for sensing when it touches something with the structure, as well as a band of golden setae below it, over its head.
        Another interesting use of setae with insects is for self defense. Caterpillars are the stars of using setae to either a.) make themselves completely unpalatable by becoming one giant cotton ball of hair, like the photo below:
Caterpillar covered in setae; its old, shed exoskeleton is to the right
         Or b.) a caterpillar can use what are called urticating hairs, which actually can cause itching and other irritation. These break off when you touch the hairs, and again help make the caterpillar as unpalatable as possible. The Douglas Fir Tussock Moth below can actually cause a significant allergic reaction if touched, or if the hairs are inhaled.
Tussock Moth. Image from http://www.fs.usda.gov/detail/r6/forest-grasslandhealth/insects-diseases/?cid=stelprdb5377760
     So...the moral of this story is that there are insects that are furry and fluffy, and may in some cases draw the same "aww, this is cute!" response as our mammalian furry friends. However, the "hairs" in insects are there for different reasons than in mammals, such as for sensing their environment or self defense against predators. Yay fluff!