Cockroaches and Springtails

Jan 11
For class we began reading the book Life on a Little Known Planet by Howard E. Evans. This book is about the magnificent natural world that our earth offers to us. The book is directed towards the general public so that they will understand the world a little more. Although Evans states that there is so much to our world which is unknown, he attempts to breakdown the known information on insects to people. Evans believes people should know more about these crawling creatures since the pyramid of numbers basically puts them near the bottom near bacterias, producers, and protists (Evans 30). The pyramid Evans describes resembles a hierarchal structure where the higher up you are among the pyramid the less populous you are. Evans wants people to see the vastness of insects among the earth, and if people recognize this ubiquitous spread of insects among the world then potentially more people will become enticed by these marvelous creatures and want to discover more about them. Evans believes people should take the time to study what the world has to offer us; what life offers us and many other organisms. Evans really digs into the insect information beginning with a chapter on springtails. Evans probably begins his chapter with this non true insect (although they are evolutionarily closely related) because these are the most numerous species on the planet besides mites, and yet ordinary people living day-to-day lives have probably never known about this animal (Evans 32). Specifically, that's exactly what Evans attempts to do throughout his book, prove to people all these unknowns about our natural world, and he starts so by talking about a creature that is everywhere and no one knows of it. I found the springtails to have some interesting information. First of all, I recognized throughout the chapter the distinctions between most insects and the springtail organisms. Springtails are missing a common evolutionary adaptation for filtering their hemolymph and uric acid. Also, springtails have six abdomen segments compared to an insect's eleven. Lastly, springtails' development as an embryonic egg is different than true insects. Springtails do not undergo the same cleavage furrow formation as insects do, and I wonder if since their cleavage is different and I know they are protostomes since insects are, but are their coelom formation different than that of a true insect (Evans 35). Besides the distinct differences between the two groups evolutionarily, springtails do have one interesting tactic that I found to be cool. All insects are very chemical sensitive through their sensory organs: antennae. their tastes, etc.; however, springtails can use their chemical senses to change their coloration and to change the composition of their blood (Evans 38). These defense mechanisms are useful throughout their survival. The mimicry the insects use hides them from potential predators and also allows them to send warning signals to predators to avoid being eaten. Another tactic the springtails use is "reflex bleeding" where they change their blood to become toxic when attacked (Evans 38). This one mechanism really impressed me because it verifies just how sensitive insects and similar groups are to chemical structures. These springtails have control over their internal system in order to allow them to physically manipulate and change the orientation of molecules within their hemolymph to become toxic. That aspect is unbelievably impressive, and these springtails need to be recognized for their success in their survival strategies.

Figure 1.

I. Jesse works within the entomology department of Iowa State University and provided the picture (above) of the springtail. 

http://www.ipm.iastate.edu/ipm/iiin/node/109

Besides just springtails, Evans, in the beginning, also addresses the cockroach. These creatures love being in places where there is an abundance of food, and most commonly they get into people's houses from their groceries (Evans 60). To think that every roach you have killed in your house probably came home with you and all of your groceries - disgusting. In addition to that fun fact, cockroaches have been experimented on to discover their intelligence. These creatures can even solve mazes and have the capability to learn without their heads (Evans 52). I wondered how these creatures can survive without their heads, do they not have a brain? Well my teacher explained to me that these specimens do have brain(s) technically. Their nervous system is not centralized since they are not evolved enough to have such a nervous system, but they have ganglions and sort of a circuit type nervous system. Imagine many brains spread throughout your body in a parallel circuit formation, since each brain is independent of the other.

Figure 2.

Above is a depiction of a simple parallel circuit. The battery would represent the roach's head, while the  four resistors would represent the roach's other brains (ganglions). If one were to go out the others would always still be functional.

http://www.physics247.com/physics-tutorial/parallel-circuits.shtml

This is how the cockroach can still function, even without its head. That is one interesting piece of information that I did not yet know, and it will serve a purpose for next time that you think you killed the pest in your house.

Figure 3.
Above are the different species of cockroaches commonly found here in America.
Image provided by the Centers for Disease and Control Prevention
http://www.cdc.gov/nceh/publications/books/housing/figure_cha04.htm

Class

Jan 8 - 9
As we began our second day of class, we went to the library to watch CSI: sex, lies, and larvae. Wow, this episode had a lot to talk about; it had its accuracies and its inaccuracies. Besides the factual information, the episode was within its first season, and it was somewhat overly dramatic in the acting. However, assessing the accuracies of the insect information I learned new things about insects and their applications that I did not know prior to the film. First, insects can be used in crime scenes and investigations to determine how long the corpse has been deceased. Investigators use a technique called linear regression to map the life cycle's of insects to incorporate that into the time of death. The application of insects and science into real life events is fascinating; besides insects being evolutionary successful creatures, we humans find them useful in numerous aspects with just this sole one technique. If people would further know the application and background information on insects it would really change the public perspective on these misconstrued victims. I know from personal experience that with just this first week of class I want to dig further and know more about these mysterious creatures than I thought possible. Another weird, but true fact I learned from the CSI episode was that forensics probably arose from the story of a man using his shovel in some distant country to determine which man in the village killed the girl. So from the beginning, someone was guilty of murdering this girl within the village, and all the men pleaded innocent. Well one innovative, early "scientist" thought for every man to hold his shovel out, and whichever shovel attracted flies that man was guilty of the homicide. Flies can detect microscopic pieces of flesh and blood that humans cannot see or detect. On the other hand, the inaccuracies are just as prevalent. One of the main characters is supposed to be sort of an entomologist, at least in respect to the crime scene investigations. He referenced the life cycle of the flies within the film, but completely skipped a phase of their cycle: the pupa(e) stage. Flies go through complete metamorphosis, which has four stages within their life. Additionally, the same character also constructed an inaccurate experiment. He deduced that the deceased female has been dead for five days using linear regression, but then later he replicates the death scene using a wrapped pig to determine its linear regression. One, the man stated previously in the film that species of flies found within the woman were found in urban areas only. While doing the experiment with the pig, he placed the pig in an abandoned rural area. Well for one the two species of flies would evidently be different then. This causes two problems: different species means different life cycles and different linear regression times; thus different times of death. Other than that large inaccuracy the film was quite entertaining compared to a regular class room setting. This class is becoming quite interesting. Following the film, our class went out by one of our dorm's lakes to look for any insects. First, we began by searching through cattails for larvae of the cattail moth that commonly inhabits our campus. These larvae are hard to find because they are so small and a pale yellow color. They hide deep within the cattail flower, and we had to pull off the spores of the cattail to find these specimens. Soon after searching for these larvae, a classmate found a couple of preying mantis nests. These nests consisted of their eggs, which will hatch in the warmth to produce preying mantis nymphs that will undergo gradual metamorphosis. Lastly, our professor allowed us to walk around and search for moth pupae within the trees. He told us that some moths/pupae have already emerged and will be within hollow trees to overwinter. We found several cocoons dangling from the trees. Specifically, one cocoon was empty, but had an exoskeleton of the larva within it. This means that this moth has already emerged and began its reproductive state. Our second day of class turned out to be quite different because you'll never know what interesting things you'll find if you look close enough. Following this day of class, our Thursday class now seems ordinary. We went to the classroom to discuss the reading which we had to complete, and then we proceeded to go outside to collect more insects. This time the insect collection was real interesting. We went into the eco scape forest to search for any kind of insect we could find in any such place like within the trees, under the logs, under the leaf litter, or just about anywhere if you look closely enough. Strangely, I found a parasitized caterpillar pupa on a leaf, but it was unidentifiable. Then after finding that, I found a pine cone with some pupa inside, and then under a rotting log I found a couple of creatures: spiders, termites, and earwigs all squirming and crawling their way through the crevices of the wood. Lastly, I found some large beetles burrowed within another rotting log.

These beetles are pretty large, and I've noticed that the male beetle has a small black horn protruding from his head. It was great to go out and find more insects, and the part that is amazing is that if you just look hard enough and close enough you would be amazed by what all the natural world has to offer.

On Being a Cold Bug

Jan 9
One of the coldest experiences that I have had was when I went camping in the woods with my friends this year. It was one horrible, cold night and none of us knew how to build a fire. We all slept in our sleeping bags, miserable because of the freezing temperatures. Once we woke up in the morning, none of us could feel or even move our toes and feet. Needless to say, it was one cold experience. Insects have to face these challenges every year in the winter. This winter especially is the coldest one I have lived through. Imagine having to be outside surviving in this climate each and every day. That is a significantly difficult trail to overcome. Insects use many adaptations and various tactics to overcome the winter such as: supercooling, hibernations, and migrations. One amazing example of an insect overwintering tactic is displayed by the goldenrod fly. As I was reading chapter 14 in Heinrich's informative novel, I quickly learned new tactics to overwinter, and this one tactic amazed me because I have never seen or heard anything quite like it before. The mature goldenrod fly lays its egg within a growing plant stem, and the new found larva secretes some chemical to induce growth, a gall, around the area the egg was injected. The tumor now becomes the new home for the larva and is in a prime location for the larva to extract any nutrients from the plant so it may survive. During the larva phase, it also chews a tunnel to the exterior of the gall using its mandibles. Then the larva goes back into the gall for hibernation until it pupates and emerges as an adult fly, who then will emerge from the gall to enter its reproductive period.

Figure 1.
Above is the gall of a goldenrod fly larva who has recently emerged, or has been eaten due to the size of the extraction site. The image below the gall is of an adult reproductive goldenrod fly.
http://www.pbase.com/laroseforest/galls (link where picture was obtained; no author)

 In addition to the golden rod flies, one other specimen was quite fascinating. Heinrich describes the banded woolly bear caterpillar as an awe inspiring creature. These larvae actually live throughout the winter, not by hibernating, but by internally adjusting their chemical composition. So the caterpillars won't freeze and die, these specimen change their chemical intercellular composition. They change their lattice formation of water so it all won't freeze and expand within their cells causing non programmed apoptosis, thus resulting in cellular destruction. These specimen chemically manipulated their internal structure within their cell not only to osmotically remove water, but also to add glycerol, which acts as a form of antifreeze. These two examples that Heinrich described fascinated me, and I decided if I was an insect I would want to choose to be the banded woolly bear caterpillar because of its unique properties of adjusting its chemical composition. After reading these different tactics and examples, a new appreciation for insects developed out of me. They are very successful creatures who can manage to do extraordinary and seemingly impossible tasks like surviving in these harsh winter conditions. Insects can live outside through the winter; how many humans can say that they can do the same? None, that is why insects are incredible specimens because they are capable of anything due to their evolutionary adaptations.

Figure 2.
Above is the image of a woolly banded bear caterpillar.
Image provided by Wikipedia
http://en.wikipedia.org/wiki/File:IC_Pyrrharctia_isabella_caterpillar.JPG

First Day of Class

Jan 7
Typically, everyone thinks first day of class is miserable, basically just like any other syllabus day. However our first day of class was something out of the ordinary. We discussed our homework and readings assigned to us the previous day. Diving into these readings, we talked about an awesome tactic insects use to overwinter: supercooling. I learned that insects can actually manipulate their internal chemical structures to survive harsh conditions. They can remove water within their cells and somehow rearrange atoms to create glycerol and other antifreeze substances to prevent freezing of their internal cells. This aspect was really fascinating because these creatures have evolutionarily gained adaptations to allow them to manipulate their chemical structures. Other insects actually allow themselves to freeze, in order to survive. These insects can survive all winter, and another aspect that is weird to think about is that every insect we see in the spring is living right now, outside in the cold. These insects can bear all these harsh conditions and still live. Another point we addressed in class was metamorphosis and an insect's life cycle. Metamorphosis is a radical change, the insect goes from its larva state to a pupa state and finally into its adult state. Through this process you have the exact same species in all three states, but they species appear physically completely different in all three states. In the larva state we're accustomed to seeing caterpillars and other worm like larva who feed all day; however, when this specimen enters its pupa state, the creature literally digests its cells (all but a remaining few). The specimen now is literally a few cells, which contains DNA, so it can begin replication and division to begin its life as an adult. The adult is drastically a new creature, but has identical DNA to the larva, which came before it. Basically, the tiny larva took its DNA and transformed itself into something new. An example is the caterpillar to the butterfly. The caterpillar and the butterfly are the exact same animal, but one is farther along in its life cycle than the other. Wow, to think that one caterpillar went through the entire process of digesting itself, and then replicating DNA and cells to become a completely new butterfly, the process is drastic. Next, our teacher brought it hissing Madagascar cockroaches. He actually let us hold them. When aggravated, we could hear the creatures actually "hiss" at us, but that is their form of breathing as they inhale and exhale the air through their abdomen. Interestingly enough, these insects have evolved so that they need no wings, and another interesting fact about them is that they are incredibly lazy and slow creatures. Also, their feet are very adhesive to complex surfaces, since the cockroaches have a similar structure to velcro on their feet; thus allowing their adhesive properties. Lastly, we went into the bio lab and observed insects up close with a microscope. Noticing all the detail the insects have is amazing. Personally, I looked at a moth under the scope, and I noticed all the hair-like protrusions on the insect, but actually these are not hairs but scales. Their entire bodies and wings have these scales, thus why they belong to the order Lepidoptera. Another cool thing about the insects that I could see magnified by the scope was their compound eyes. Each individual eye has thousands of compounds on it, and each of these compartmentalized cell itself is actually an eye. So on what seems like their round surface of one eye, in reality, is actually a cluster of hundreds or thousands of eyes.

The detail in insects up close is amazing because I took for granted earlier all the aspects about them, but now appreciate their aspects and their evolutionary adaptations for survival in overwintering. This detail is what makes the insects so successful as specimens on earth, and I am beginning to see how adversely equipped just these creatures are.

Initial Thoughts on Insects

January 3, 2014
Until high school I always believed that insects were disgusting creatures that were full of diseases and different bacteria. My reaction was always to get rid of them: squish them with a shoe, pick them up in a kleenex, and flush them down the toilet. They were creatures to be avoided. They always crawled around, hid in the darkest places, and would show up at the most inopportune moments. Every moment was inopportune because no one wanted these foul creatures around; they were disgusting. Some films like The Bugs Life portrayed the innocence of these creatures, while other films such as Spider portrayed the arachnids and similar creatures as dangerous and repulsive. Of course the scarier movie had the most significant impact on my perception on insects. When I was in the seventh grade, one of my teachers, Ms. Jamie Beale, used to actually eat insects. She would bake breads that contained larvae, mill worms, and other such creatures. She said eating insects was a great source of protein, and she had absolutely no problem eating them. I thought to myself that I would never eat such a creature not just because it is disgusting, but also because I couldn't get over the texture of chewing through their exoskeletons. Following middle school, my high school years brought to some degree of studying insects. Going into high school, I maintained the same stereotypical mindset on insects. During my high school years, I took two biology classes, and one of my teachers graduated with an entomology degree. He taught us evolutionary standpoints during AP Biology, and when I learned about insects in that perspective a new appreciation developed. At the end of one of my biology classes, we had to complete an insect collection of ten bugs. Specifically, I remember catching my lunar moth for that project. When someone thinks of a moth most people probably think of the little brown nuisances that arrive when they have their back porch lights on. However, this moth is completely different; they are much larger than those regular moths, and these creatures are beautiful in color. They glow with a fluorescent green that is amazing to just see and watch. After completing my insect collection, I matured a little in the handling of insects and my maturity grew in my mind as well. I wasn't as afraid of insects as I was, but I still found some creatures repulsive. Going out catching and discovering these bugs made me realize their innocence, most mean no harm at all, but are only competing to survive within their niche. Insects are remarkable, relative to their size; the fact that insects have been around countless centuries is amazing. They have not biologically gone extinct, but keep evolving to be more adapt to the environment. These species have dominated earth, and due to this and their ability to adapt, appreciation is in order for such biological success. Nonetheless, some species of insects are still abhorrent such as the cockroach, but most are seemingly harmless creatures and I learned to appreciate their successful presence on earth. Throughout the upcoming entomology course, I hope to learn more about insects so that I can appreciate them even more than I already do in their evolutionary aspect.