On page 100-102 from chapter 5, William Eberhard (2000) describes an interesting relationship between a female wasp parasite, Hymenoepimecis a. and its spider host, Plesiometa a. Although these species do not occur in southern Africa, they illustrate an interesting instance where an insect parasitoid is able to alter the behavior of its spider host to the finest degree. The orb spider is stung while on its web and is temporarily paralyzed while the wasp lays her egg on it. The spider then recovers and goes about its life with the newly hatched wasp larva feeding on it by sucking its haemolymph (spider "blood"). For about 7 to 14 days, the spider continues building its usual orb webs for prey capture. However, in the evening of the night when it is to be killed by its wasp parasite, the spider weaves a different web, designed specifically to suit the purposes of the wasp. The wasp larva then molts, kills, and consumes the spider and pupates, suspending itself safely from its custom-built cocoon web. The behavior of wasp parasite relates to big idea 4 (Biological systems interact, and these systems and their interactions possess complex properties), since this symbiotic relationship between these two organisms portrays a biological system of how a parasite is able to change the behavior of its host. On the other hand, it also relates to big idea 1 (the process of evolution drives the diversity and unity of life), since the wasps survive and reproduce by its own unique reproduction.
Many complex symbiotic relationships exist in an ecosystem, and feedback control systems play a role in the functioning of these ecosystems. How does the female Hymenoepimecis wasp develop its selective advantage, unlike any other wasps? What are some examples of parasitism other wasp developed? In what ways could this symbiotic relationship be selective disadvantages? Discuss what kinds of biotic and abiotic limiting factors (density dependent and density independent) might affect population size of wasp. Then relate this topic from either sources: other symbiotic relationships given in The Survival of the Sickest or the materials from unit 5: Ecology and Behavior.
(Hyung Eun Lee- helee4@students.d125.org)
(Hyung Eun Lee- helee4@students.d125.org)
After injecting the spider the living larva "the larva somehow biochemically manipulates the spiders nervous system causing it to perform one small piece of a subroutine... repressing other routines" page 102 which is a theory as to how the Hymenopimecis larva is able to control the spiders, and basically make the spider into its own personal slave, preparing it to voluntarily sit there and be consumed. According to the article online, unlike other wasps which lay thousands of eggs into their host Hymenopimecis wasps only lay one. If the Hymenopimecis wasp simply lay their one precious egg out in the wild, the higher the chances that a predator will eat the egg or it will simply get squished. To be able to survive, which goes along with big idea number i, these wasps developed the ability to lay their egg into a spider. The spiders ability to build a web was very abilitative to the survival of the new born larva since spiders are the only creature that have the ability to build webs, webs facilitate trapping food, protection from other things, since it is usually built in a high place. Other wasps plant many eggs so they don't need the extra boost to be able to survive since to continue the species genetic line, only one out of those thousands has to survive, yet for the Hymenoepimecis wasps inability to produce more than one places them at risk of quick extinction if it were not for this ability. Another example of a wasp using a host for its own benefit is Trichogramma lays its eggs in caterpillars or "Copidosoma spp. (Chalcidoidea, Encyrtidae), undergo a process called polyembryony, whereby an egg inserted into a host divides and gives rise to hundreds of larvae". For any wasp population if the population of the hosts reduce in numbers then the wasps don't have as many habitats to hold their developing larva eggs. Natural disasters that cause the reduction in numbers can also cause the numbers of both host and larva to parish. For example a flood could wipe out a vast majority of the caterpillars for say. Or a hurricane could destroy the habitat of the spider which carries the larva. Even afterwards, whatever the larva eats could decrease in size which affects the amount of survival within the specie. Not only do wasps use other insects to survive and continue on, but in the survival of the sickest sharon talks about how Tgodii parasistes that undergo sexual reproduction within only cats, Tgodii is able to host other organisms tho. Tgodii can affect humans. He says that about 20 percent of the american population is actually infected by t godii and 90 percent in france! page 106. It does this, when the infected cat expulses uneeded mass from its bottom, the human who is picking up his or her cats manure could possibly have a cut or an opening, which allows t godii to enter, which is distributed throghout the body through the bloodstream, where they stay in the brain and muscle cells. T godii can trigger schitsophrenia. Parasites are able to ensure their survival by living in other organisms before they hatch. http://bio390parasitology.blogspot.com/2012/03/hymenoepimecis-argyraphaga.html
ReplyDeletehttps://insects.tamu.edu/fieldguide/cimg329.html