Insect Camouflage & Coloration

Cryptic coloration, body shape, and other adaptations are often common place in the insect world.  While most of us are familiar with walking sticks looking like tree or plant stems a variety of other insects have unique strategies for survival.  One group of insects that often can have rather grisly way of camouflaging themselves are assassin bugs.  The assassin bug, Acanthaspis petax, has the perhaps one of the coolest body armors in the natural world.  What is it?  A. petax uses the dead carcasses of ant prey to cover its body.  Research completed in 2007 found this corpse filled defense helps repel spiders from preying on them (Stromberg, 2012).

                                                          Photo by Mohd Rizal Ismail

Another unique way of protecting yourself in the insect world is to resemble something big and tough, such as a snake. A number of caterpillars of moths and butterflies mimic the appearance of snakes to deter predators.  One such caterpillar is the spicebush swallowtail butterfly larva (Beiser Field Station, 2008).


Image credit: Beiser Field Station

Works Cited:
Spicebush Swallowtail. (2008, October 7). Retrieved December 9, 2014, from http://www.marietta.edu/~biol/biomes/spicebush.htm

Stromberg, J. (2012, May 8). This Insect Uses Its Victims' Carcasses As Camouflage. Retrieved December 9, 2014, from http://www.smithsonianmag.com/science-nature/this-insect-uses-its-victims-carcasses-as-camouflage-83656246/?no-ist

Gut bacteria that can Degrade Plastic

Indian mealmoths (Plodia interpunctella) have recently been discovered to harbor bacteria which can degrade polyethylene.  The bacteria in question, a Bacillus and Enterobacter species, were isolated from the guts of P. interpunctella and demonstrated significant degradation of polyethylene with "tensile strength dropped by 50%, and their ability to repel water droplets fell by 30%. And after the microbes grew on the polyethylene for 60 days, the mass of the plastic films decreased by 10%, and the molecular weights of the polymer chains dropped by 13%" (Pelley, 2014). 

Other studies complete 2011 found bacteria living in shallow pits on polyethylene  plastic found in ocean waste.  Researchers indicated that, " almost 25% of the baceteria on one polyethylene surface were vibrios, bacteria from the same group as the cholera bacterium" (Zaikab, 2011).

Electron microscopy reveals the inhabitants of a plastic bag fished from the Sargasso Sea.T. Mincer/G. Proskurowski

Works Cited:

Pelley, J. (2014, December 4). Pantry Pests Harbor Plastic-Chomping Bacteria. Retrieved December 5, 2014, from http://www.scientificamerican.com/article/pantry-pests-harbor-plastic-chomping-bacteria/

Zaikab, G. (2011, March 28). Marine microbes digest plastic. Retrieved December 5, 2014, from http://www.nature.com/news/2011/110328/full/news.2011.191.html

3 Facts about Turkeys

Thanksgiving is right around the corner and in preparation for the holiday season I've decided to list a few facts I found interesting about turkeys (Meleagris gallopavo).

1.  While most of us are familiar with the "gobble" sound made by turkeys, these birds also make a host of other calls.  According to the Cornell Lab of Ornithology Website, male turkeys "gobble" to attract mates, females and males "purr" while on foot, and courting males produce a "chump" sound which is not well understood (2014).  If you're curious about how these actually sound as well as other bird calls I highly recommend you visit the Cornell Lab page here.

2.  Fun fact, Benjamin Franklin wanted turkeys to be our national symbol, not the bald eagle and lamented the choice. an Article in Slate Magazine, by Nicholas Lund (2014), cites a letter from Franklin stating, 

  "For in Truth the Turkey is in Comparison (sic. eagle) a much more respectable Bird, and withal a true original Native of America. He is besides, tho’ a little vain and silly, a Bird of Courage, and would not hesitate to attack a Grenadier of the British Guards who should presume to invade his Farm Yard with a red Coat on."

3.  Every year the President of the United States pardons a turkey....... This year the lucky bird who won't be for dinner is from Ohio.  Read about it here.

 

Image:  http://www.cashstore.com/blog/thanksgiving-costs-will-rise-in-2012/

Works Cited: 

Lund, N. (2014, November 25). Benjamin Franklin’s Bizarre Symbology. Did He Really Admire the Turkey? Retrieved November 26, 2014, from http://www.slate.com/articles/health_and_science/holidays/2013/11/benjamin_franklin_turkey_symbol_why_he_hated_the_bald_eagle_for_the_great.2.html

 Wild Turkey. (n.d.). Retrieved November 26, 2014, from http://www.allaboutbirds.org/guide/Wild_Turkey/sounds

Nature Deficit Disorder

Recently, a number of documentaries have been published alleging that teens and children today lack adequate exposure to nature.  The term, "Nature Deficit Disorder", first stated by Richard Louv in his book, "Last Child in The Woods" has become the phrase associated with the lack of outdoor play in children.  According to Louv, "Kids who do play outside are less likely to get sick, to be stressed or become aggressive, and are more adaptable to life’s unpredictable turns." (Egan, 2012).  What sort of evidence supports going outside more?  Studies completed by Atchley & Strayer (2012) on individuals going on hikes state: 

"Our results demonstrate that there is a cognitive advantage to be realized if we spend time immersed in a natural setting. We anticipate that this advantage comes from an increase in exposure to natural stimuli that are both emotionally positive and low-arousing and a corresponding decrease in exposure to attention demanding technology, which regularly requires that we attend to sudden events, switch amongst tasks, maintain task goals, and inhibit irrelevant actions or cognitions"

  Despite an apparent correlation between nature and increased cognitive advantage the study failed to  conclude if exposure to nature or decreased use of technology resulted in a cognitive advantage.  Do you think kids aren't exposed to enough nature?  

Below are two trailers for documentaries addressing "Nature Deficit Disorder". 

Trailer 1:  "Mother Nature's Child"

Trailer 2:  "Play Again"

Works Cited:

Atchley, R., & Strayer, D. (2012, December 12). Creativity in the Wild: Improving Creative Reasoning through Immersion in Natural Settings. Retrieved November 20, 2014, from http://www.plosone.org/article/info:doi/10.1371/journal.pone.0051474

Egan, T. (2012, March 29). Nature-Deficit Disorder. Retrieved November 20, 2014, from http://opinionator.blogs.nytimes.com/2012/03/29/nature-deficit-disorder/?_r=0

New invasive species found in Pennsylvania

Invasive species can be destructive forces in natural ecosystems and agricultural settings.  Recently, a number of counties in Pennsylvania have been put under quarantine as a non-native insect species was detected. The insect species in question, commonly known as the spotted lanternfly (Lycorma delicatula) , is native to China and southeast Asia.  The insect belongs to the Order Hemiptera, and is in fact, not an actual fly but a type of planthopper belonging to the family Fulgoridae. According to Dara (2014), "Spotted lanternfly feeds on a variety of host plants including fruit trees, ornamental trees, woody trees, and vines.  Apples, birch, cherry, dogwood, grapes, Korean Evodia, lilac, maple, poplar, stone fruits, and tree-of-heaven are among more than 70 species of hosts attacked by this pest."  This wide host range could become problematic for a number of agricultural crops if the spotted lanternfly were to become established in the United States. 

For more information & tips for identifying L. delicatula visit: 

http://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=15861

http://www.farmingmagazine.com/blog-8053.aspx

Works Cited:

Dara, S. (2014, November 7). Spotted lanternfly (Lycorma delicatula) is a new invasive pest in the United States. Retrieved November 12, 2014.

Malaria & Mosquitoes

Many insects are vectors of disease. Perhaps the most infamous of the insects associated with disease are flies in the family Culicidae or more commonly known as mosquitoes.  Mosquitoes vector a wide assortment of disease causing protozoans, viruses, and bacteria.  Malaria is perhaps the most deadly vectored disease from mosquitoes.  The chart below from the CDC (2012) provides a quick overview of how the Plasmodium completes its life cycle in humans and mosquitoes in the genus Anopheles.

Mosquitoes are crucial for the pathogens transmittance to new host as the mosquito releases new "spores" to hosts when they take a blood meal.  The CDC website also provides a more detailed overview of the infection stages and can be found in the works cited page.  Malaria is a serious problem in my countries and deserves more public attention in the United States.

Works Cited:  

Malaria: Biology. (2012, November 9). Retrieved October 27, 2014, from http://www.cdc.gov/malaria/about/biology/

Insects and Water Quality

Insects are ubiquitous.  They inhabit nearly every habitat on the planet including freshwater lakes and streams.  Having clean freshwater is not only important for human consumption but for the general health of aquatic ecosystems.  Many insect species can be indicators of clean water as their larvae develop over extended time periods in freshwater.  Of these species, insects in the orders Plecoptera, Ephemeroptera, and Trichoptera are often associated with clean, fast moving waters.  By contrast, many Dipteran species such as midges and mosquitoes can thrive in sub-optimal conditions with little oxygen or significant organic nutrient waste.

For more information regarding insects used in water quality testing visit: EPA: Macroinvertebrates.  

Insects as food

While it may seem repulsive to some, the consumption of insects or entomophagy is a common practice in many countries around the world.  Insects when compared to other sources of meat require less natural resources and have pound for pound more protein than other more common meat sources (Holland, 2014).  Live Science author, Marc Lallanilla (2013), highlights 7 insects that we will more than likely be eating in the near future.  Of these insects listed here, meal worms are probably the most widespread and type of insects a budding entomophagist would consume.  I personally have no objections to consuming insects for food and have tried a number of different dried samples of meal worms, wax worms, and crickets. The wax worms were particularly tasty and reminded me of a cheese curl.  I provided a table showing the protein, fat, and other nutrients in various organisms from Slate.com.  You can check out the article here.

So would you eat insects?  I know I would if I could readily purchase them at the store like a steak or hamburger patty.  Let the food revolution begin!

Works Cited:

Holland, J. (2013, May 14). U.N. Urges Eating Insects; 8 Popular Bugs to Try. Retrieved October 21, 2014.

Lallanilla, M. (2013, October 1). 7 Insects You'll Be Eating in the Future. Retrieved October 21, 2014.

Martin, D. (2014, April 28). Stop Adding Protein Powder to Your Post-Workout Shake. Add Bugs Instead. Retrieved October 21, 2014.

Insect Respiration

Insects respire through opening in the sides of the abdomen or thorax known as spiracles.  Spiracles regulate the flow of oxygen and carbon dioxide gases within the insect tissues.  Unlike humans which use blood to transport gases both to and from the tissues, insects do not use their blood (hemolymph) for this purpose.  Instead oxygen gas passes directly into the tissues through a series of hollow tubes called tracheoles.

Microscopy of Insect Spiracle (Kelly, Fellers, & Davidson, 2003)

Insects that are aquatic have a number of other modifications for accessing oxygen from water.  In some cases external gills, such as those seen on a mayfly larva, are used to gather oxygen from running water.  Air bubbles, thoracic pumping, and breathing tubes are also employed by insects that live aquatic or semi-aquatic lives.  For more information about insect respiration visit this link: Insect Respiration

Works Cited:

 Kelly, C.D.,  Fellers, T.J.,  & Davidson, M.W. (2003)Molecular Expressions: Science, Optics & You - Olympus MIC-D: Oblique Gallery - Insect Spiracles. (n.d.). Retrieved October 13, 2014.

Insect Development: Complete Metamorphosis

Insects exhibit a diverse array of developmental strategies.  The development most commonly associated with insects is the life cycle of a butterflies in which an egg hatches into a caterpillar, the caterpillar creates a cocoon or chrysalis, and then the adult butterfly emerges.  This type of development exhibited by butterflies is termed holometabolous development.  Many insects exhibit holometabolous development such as beetles (Coleoptera), flies (Diptera), Dobsonflies (Megaloptera), and a number of other insect orders.  Insects that have complete or holometabolous development look vastly different when comparing larval forms and adults.  Also all holometabolous insects have a pupation period where physiological changes occur in the last instar that lead to adult characters.

Confused Flour Beetle Life Cycle (Baldwin & Fasulo, 2014)

Control of when to pupate or molt is largely controlled by the hormones ecdysone and juvenile hormone.  As the name implies, juvenile hormone promotes larval characteristics and inhibits molting or pupation.  By contrast ecdysone promotes molting, pupation, and the development of adult characteristics (Meyer, 2006).  For a more thorough introduction to molting and the hormones associated with it visit this link. 

Works Cited: 

Baldwin, R. & Fasulo, T.R. (2014) "Featured Creature: Confused Flour Beetle".  http://entnemdept.ufl.edu/creatures/urban/beetles/red_flour_beetle.htm

Meyer, J.R. (2005).  "The Endocrine System: Hormonal Control of Molting & Metamorphosis" North Carolina State.  http://www.cals.ncsu.edu/course/ent425/tutorial/endocrine2.html

Insect Vision

Insect vision unlike human vision uses multifaceted lens in a structure referred to as compound eyes.  These compound eyes are composed of smaller units called ommatidia.  Each ommatidium is composed a retinal cell, a crystalline cone, up to eight rhabdomeres and a sensory neuron.  Light collected by the ommatidia are then used to generate a mosaic image in the insect brain. Many insects also have smaller light sensing structures called ocelli.  Ocelli are often found in larval forms of holometabolous insects and are primitive eyes used primarily for sensing changes in light as they lack .

Many insects can see color as well as perceive wavelengths of light imperceptible to the human eye.  For example, honey bees (A. mellifera ) can detect ultraviolet light.  The additional wavelengths often can provide "nectar trails" that are invisible to the human eye (Stanley, 2014).  A comparison of floral colors between humans and honey bees can be found here.   Also, if you've ever wanted to experience vision through the eyes of a bee (because who hasn't, right?) visit this site.

Works Cited:

Stanley, C.  2012.  Honey bee navigation.  Utah PESTS News Vol. IV, Winter 2012.

Why are Puppies so darn cute?

Baby animals are adorable including those of the human variety.  If you don't believe me just take a look on YouTube at the huge number of videos of babies doing cute things like laughing or puppies rolling on the ground.  Why do we find these simple acts so "precious" in babies but not in adults?  Believe it or not there is an evolutionary link between cuteness and human babies.  Famous evolutionary biologist, Stephen Jay Gould wrote a rather popular essay detailing the evolution of the Disney character, Mickey Mouse, from a pointy nosed rat to the the lovable round headed mouse most of us associated with the character.  The essay, readily found online explains that many of the baby critters we find so precious have enlarged heads and eyes much like human babies, are relatively uncoordinated, and have large deposits of fat.  If these characters sound familiar, they should as they could describe a human baby as well as an adorable panda cub.  Humans are hardwired to care for children to further the species.  It just so happens that being cute helps promote care of children until they no longer need parental care.  This love of tubby little big headed critters spills over into our selection for pets and what we choose to eat or not eat.  Go give your puppy a hug.

Works cited:

Stephen Jay Gould. "A Biological Homage to Mickey Mouse." Ecotone 4.1 (2008): 333-340.

If a Problem Comes Along You Must Google It!

The phrase, "Just Google It", is as common place as internet access through out the United States.  The vast, tangled web, of information provided on the web as been both a blessing and a curse for those seeking knowledge on the internet.  Recent research has found that information "googled" is less likely to be remembered than other traditional forms of learning (Krieger, 2011).  Is this necessarily a bad thing? And our we as the human race becoming sequentially dumber as more and more information becomes available online?  I suppose it depends on how someone views information previously stored in memory being allocated to the "cloud".  Wegner & Ward (2013) through experimentation found that individuals rely on the internet to play the role of an "all knowing" friend.  This "friend" can then help answer hard to remember facts or information that previously may have been committed to memory. Wegner & Ward (2013) also found that individuals allowed to use Google to find answers felt smarter than those who were not able to search answers from the internet.  This false cognitive self esteem made individuals feel smarter despite the fact they knew less information and relied on Google as a memory source.  Google is so pervasive I even have to capitalize it......

Works Cited:
Krieger,L.M.  Google is changing your brain, study says, and don't you forget it. (n.d.). Retrieved September 3, 2014, retrieved from http://www.mercurynews.com/science/ci_18478827

Wegner, D., & Ward, D. (n.d.). The Internet Has Become the External Hard Drive for Our Memories. Retrieved September 3, 2014, retrieved from  http://www.scientificamerican.com/article/the-internet-has-become-the-external-hard-drive-for-our-memories/?page=3

Blogs About Science

There are a number of places on the web that collect some great science blogs.  The topics of these blogs are written by practicing scientists in their respective field or by accredited reporters.  Regardless of the source, both provide citations and helpful links to past blog posts and scholarly research.  Below I list a few places you can find blogs to follow.

Scientific American Blogs:
http://blogs.scientificamerican.com/

The blogs found on the Scientific American Magazine website happen to be my favorite source to find blogs about just about anything science related.  They are updated frequently and the wide range of topics available make it a great source.

Discover Magazine Blogs:
http://blogs.discovermagazine.com/

Discover Magazine is also a great source for a variety of reporter and scientists alike.  While the set up for both Discover and Scientific American Blog pages are similar I tend to favor Scientific American.  My bias could come from the fact I find Scientific American magazine to be a better science magazine. Despite my bias both sources are great place to skim new blogs or find a blog to follow.

Smithsonian Blogs:
http://nmnh.typepad.com/100years/

A final site that I like to look over is the Smithsonian Blogs.  These blogs are quite lengthy and often provide insights into the experiments and finds of scientists associated with the museum.  The one draw back to these blogs is they can be very specific and may dissuade a casual reader.

Hopefully you read or follow some of these blogs as it is a great way to keep track of the latest developments in various fields of science.

Invasive species...coming to a town near you

Invasive species are a significant problem world wide.  Invasive species can displace native species, disrupt sensitive ecosystems, and cause serious economic damage to important agricultural goods. While the list of invasive species is quite large in the United States, I would like to highlight two examples of invasive species found in the state of Ohio.

 Invasive species #1: Zebra Mussels

Zebra mussels were first introduced in the Great Lakes from ship ballast from western Europe.  These mussels are prolific reproducers and have few if any natural predators.  Zebra mussels adhere to various substrates and clog water intake pipes and other man made structures.  They also have displaced a number of native mussel species.  A brief summary of some of the damaging effects of zebra mussels can be found here: Zebra Mussels in Lake Erie

Image of Zebra Mussels on a Current Meter (image credit: NOAA)

Emerald Ash Borer

Invasive species #2: Emerald Ash Borer

Emerald ash borers are beetles in the family Buprestidae that are native to Asia. As the name implies, emerald ash borers bore holes into the wood of  ash trees.  Eggs of emerald ash borers hatch from crevices in the bark of trees and larvae burrow into ash trees making galleries in the wood.  Larvae feed on tree phloem and disrupt the ability of trees move nutrients.  Emerald ash borers are found in all parts of Ohio and the moving of firewood is a common way in which eggs and larvae are moved into new areas that may not have been exposed.  A number of reporting and identification cites exist.  See here: Ohio Dept. of Agriculture and here: Ohio State Extension Office

For more information on invasive species in Ohio see here: Invasive Plants and here: Ohio Department of Natural Resources (Invasive Species)

Bacillus thuringiensis...more than just for corn.

One of the hot button issues among the general public is the use of  bio-engineering to modify organisms or GMO's.  While genetic engineering can take many forms, plants intended for human consumption are commonly the most scrutinized GMO's.  Perhaps the most infamous of these is Bt (Bacillus thuringiensis) corn.  Bt Corn is corn that has been modified with genes from the endotoxin producing bacterium, Bacillus thuringiensis (Bt).  This bacterium and it's various strains have been used directly as a biopesticide (endospores) for a number of years with different strains proving to be more effective at insect suppression than others. In most cases, as can been seen in the table below, Bt is not spliced into a plant genome but applied to plants and other surfaces with the purified endospores sprayed much like a traditional pesticide.

Table 1. Primary strains of Bacillus thuringiensis used in managing insects.

Bacillus thuringiensis strain (Common name)	Susceptible insects
aizawi	Many Lepidoptera larvae
kurstaki	Many Lepidoptera larvae
israelensis	Larvae of mosquitoes, black flies, fungus gnats
japonensis	Larvae of scarab beetles (Coleoptera: Scarabaeidae)
tenebrionis (san diego)	Larvae of leaf beetles (Coleoptera: Chrysomeldiae)
CrylAb delta-endotoxin1	Many Lepidoptera larvae
Cry3Bb1 variant1	Corn rootworm larvae (Coleoptera: Chrysomelidae)

¹Only used in production of genetically modified crops (Cranshaw, 2014)

The application of  Bt as a sprayed biopesticide and not spliced into plant genomes may be surprising  to some individuals.  In fact, Bt is the most widely used biopesticide in the world. An excellent overview of how and when Bt is used is provided here: Bt fact sheet.  Also, despite many people's fear of Bt crops, endospores of Bt have been applied to organic and commercial crops for years.  For even more details about Bt visit: Bt & Organic Crops.  

Despite the  long safety record for Bt products fear of eating or using products with Bt remains.  Hopefully, this blog post provided a short factual introduction to the uses of Bt in modern agriculture for the uninitiated.  

Scooby-Doo and Using Observations

  I'll admit I'm a bit skeptical about this whole "blogging" business.  Is it just a journal or diary?  I suppose it could be, but I believe it can be a tool for sharing relevant ideas and opinions about science.  Seeing as I am requiring my students to keep and maintain a blog (sorry kiddos), I figured I should have to keep one as well.  I intend to post at least once a week about a some topic in science I find interesting or controversial.  For my first post I want to talk about Scooby-Doo.  Yes, the cartoon with the talking dog and the Mystery Incorporated gang.  What does a talking dog and a bunch of badly dressed teens have to do with science?  Aside from the impossible escapes from the "monsters" and the talking dog, Scooby-Doo and the gang (minus Shaggy & Scooby) don't believe that actual monsters are responsible for any of the crimes or hauntings.

Instead they question and try to find rational observation based evidence to describe what is occurring.  In my opinion, this is one of the critical aspects of all sciences; to provide observable and measurable descriptions of natural phenomena.  

What do you think?  Am I completely off my rocker? (likely) Or can Scooby-Doo actually help young kids realize that natural phenomena can be explained by natural means instead of the supernatural?  If you're feeling nostalgic go and watch an old episode of Scooby-Doo and see how they look for clues, gather evidence, and explain the mystery as really just a natural phenomena.  

If you're really into Scooby-Doo check out some of these Scooby-Doo and science links:  

Scooby-Doo's speech disorder.

The Corruption of Scooby-Doo