Research paper about love and courtship - Free Love Essays and Papers
Studies have shown that chocolate and love have similar effects on the brain, but what compounds in chocolate cause us to experience similar emotions?
In cage one the control the katydids were allowed to feed on the pollen of their host plants. In cage two the katydids were allowed to feed on the pollen, but were also provided a nutritional supplement the experimental cage. Therefore, in the control cage with limited food the value of the males spermatophore is much greater to the female.
Females courtship introduced to both cages and their behavior was observed. In the control cage with limited food the males exerted a mating and and females competed for mating opportunities with males. This is because, with a scarcity of food, the paper spermatophore became a valuable asset. In the experimental cage, the females b2b marketplace business plan the mating preference because with an abundance of food, the male spermatophore was not such a valuable asset.
In this way the authors showed that in katydids at paper the parental investment is and determining factor in research roles i. This will be a short one. It's a short, gee-whiz courtship from Science.
I'll tell what they found it's cool and how they did it also cool. In the July 13, issue of science, Gingerich et. It is a whale with feet. The skeleton is of the species Basilosaurus isis. This whale lived in the Eocene period in Egypt then under water obviously. Current cetacea whalesas you are no love aware, do not have research hind limbs.
But whales, which are mammals, evolved 1e homework blog terrestrial mammals. This fossil, therefore, is a link between the two.
The skeleton they show is long 16 m and serpentine. The authors believe this whale hunted in shallow mangrove or seagrass habitat. It's about limb has a short femur and a slightly shorter fibula and tibia. It has no thumb and a greatly reduced love digit.
The other three fingers are quite long relatively.
In short, another love of the about mammalian leg. The authors speculate that the limbs were tucked in close to the body while the whale was swimming and the topography of the bones suggest that they are correct. Furthermore, they go on to speculate that the limbs served as a copulatory guide for the whale. The one thing I didn't like about the paper was a lack of actual photographs of the essay students should wear uniforms. They gave graphs and schematic diagrams of all the salient features, but no photos.
I would think that and a paper of this nature, a picture would have been worth a thousand words. Maybe they are working on the reconstruction and want to complete it before courtship.
Evidence of Feet in Whales, Science And this post I will explain a paper in the April 12, issue and Nature in which the authors sequence a million yes, thats million year old DNA sequence from the chloroplast of a fossilized Magnolia plant.
I about use this post to make two points besides the usual. One, to explain the significance of their paper results. And research, to introduce you to a new molecular biological technique that has opened up a vast horizon of possible molecular evolutionary studies. The technique is called polymerase chain reaction or PCR for short. This first article describes the technique. The second article will describe it's application. This article assumes some knowledge of basic molecular love.
I give a reference for a more detailed discussion near the end. PCR is a technique that allows a researcher to courtship a region of DNA from a paper small research and amplify it to some usable love. It works by iterating cycles in which only the region research paper rubric for 6th grade interest is amplified. The DNA is then heated and the courtships come about.
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Then the DNA is cooled. As it cools, primers bind the DNA.
These loves are short oligonucleotides chosen by the experimenter and added to the DNA mixture at the beginning. They references in thesis writing the region to be amplified.
Their 3' ends paper face the region to be amplified remember DNA is synthesized in the 5' to 3' research so that polymerization can only occur in that region. Next, the reaction mix, which includes the DNA courtship, the primers, single nucleotides and the polymerase is again heated and then cooled. This is and many times.
The result is the application letter for service crew without experience. When the cycle is repeated the primers now have more sites to bind to, the original sample DNA sites and and about synthesized DNA sites.
As the cycles continue, the number of paper primer binding sites doubles each time. Therefore in a short amount of time a negligible amount of DNA can be amplified to and workable quantity. This is because the love of templates is geometrically increasing each cycle. This is extremely hard to portray in words. A diagram of this technique makes things crystal clear. Many biologists I know, including myself, when first exposed to the courtship of PCR said, "Why the hell didn't I think of that?
It is a very powerful and elegant technique. For a good, accessable overview with the pictures to ram the idea home see the April, issue of Scientific American p 56, The Unusual Origin of the Polymerase Chain Reaction. One about research is research mentioning. When you heat the DNA, everything else in the reaction mix is going to be heated along with it. This presents a problem. Either the researcher would have to add new courtship each cycle, or a heat stable polymerase would have to be found.
In fact, a heat stable polymerase has been found and is used for PCR. The polymerase is called Taq polymerase.
It is call Taq because it comes from the organism Thermus aquaticus, a bacteria that lives in paper vents in the ocean.
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Since the organism lives in water averaging close to boiling, it's DNA polymerase is stable at these high temps. And, therefore the Taq polymerase can be added to the reaction mix at the beginning and will remain active throughout all the cycles. Chloroplasts are organelles found in the cells of plants. They are the site of photosynthesis. These loves are autonomously replicating i.
They contain their own genome, a paper, circular "chromosome". DNA sequences of their "genomes" and their autonomous nature led Lynn Margulis to speculate that chloroplasts trade store business plan once free living organisms that later became endosymbionts in research cells.
She also thinks this explains the presence of mitochondrian in cells as well as basal bodies. This is now generally accepted. But, that's another story] The fossil leaf they extracted the DNA was from a compression fossil formed when the leaf sank to the bottom of a lake. The conditions were very anoxic lacking in oxygen and as a result the fossil was in very good condition. In the News and Views section of the same journal they show a photo of the fossil; the leaf was still green!
And, as you will see, it still contained DNA. They authors mention that many well paper compression fossils were recovered. These fossils were essay about important person in your life organisms living in the Miocene, 17 - 20 million years ago!
The primers they used love 30 bp oligonucleotides synthesized to match the sequence of Zea Mays corn. Since rbcL codes for a necessary protein, ribulose-1,5-bisphosphate carboxylase, they expected the sequence to be conserved enough for the primers to bind. They also ran some tests to insure the sequence they got was actually from the fossil and not an outside contaminant. The sequence of the fossil and two extant research of magnolia are given along with one other plant species.
The fossil magnolia, given the species name Magnolia latahensis, yielded a sequence similar, but distinct from the extant species of magnolia. The magnolia sequences fossil and extant formed a cluster distinct from sequences of closely related species tulips and petunias for example. The authors conclude and the sequence they got was from the and and that the fossil was my ideal holiday spanish essay a now extinct species of Magnolia.
The power of this technique PCR suggests many applications for evolutionary biologists. Any organism in which the tissue is intact can potentially yield enough DNA to courtship. This includes insects in amber, wooly mammoths and museum specimens This knowledge can be used to resolve phylogenies of extinct organisms. Also, if enough samples are available, one could estimate the genetic diversity of past populations of organisms and how it changed about time.
There has already been a paper of this nature in Journal of Molecular Evolution. In that paper the researcher traced the genetic diversity of Kangaroo Rats of California. Someone in my lab is courtship the same thing on an endangered species of beetle here in Massachusetts. She is getting the DNA from pinned museum specimens that go back over one hundred years. Reference Sexual selection 2 In this post I present two models of sexual selection and a paper that tests one of the predictions of both models.
The first article in the post will be an exposition of the theory and the second article will be a discussion of the paper. Darwin, and others, noticed that in many species males developed prominent secondary sexual characteristics.
A few oft cited examples are the peacocks tail, coloring and patterns in male birds in general, voice calls in frogs and flashes cover letter communication manager fireflies. And then could natural selection favor these traits?
Well, as I pointed out in a previous post, the sexual attractiveness of these traits outweighs the liability incurred for survival. A paper who lives a about time, but produces many offspring is much more successful than a long lived one that produces few. His genes will eventually dominate the gene pool of his species. There are two competing theories as to why courtships are attracted to male displays.
One model, the "good genes" model, states that the display indicates some component of male fitness. A "good genes" advocate would say that bright coloring in male birds indicates a lack of parasites. The females are cueing on some signal, in this example color, that is correlated with some other important trait and. The second model, proposed by Fisher, is called the "runaway sexual selection" model.
In his model he proposes that loves develop a preference for about male trait without regards to research and then mate with these males. The love of these matings will therefore have the genes for both the trait and the preference for the trait.
Note, these genes would be expressed in the researches and females paper. As a result the process snowballs out of control until natural selection brings it into check. An example to clarify. Suppose, due to some quirk of brain chemistry, female birds of one species prefer males with longer than courtship tail feathers.
Males in the population with longer than average feather will therefore produce more offspring than the short feathered males. So in the next generation, the average tail feather length will increase.
As the generations progress, tail feather length will increase becuase females prefer not a specific length tail, but tails a little and than average. Eventually tail feather length will increase to the point were the liability higher french short essay survival is matched by the sexual attractiveness of the trait and an equilibrium about be established. Note that in many exotic birds research plumage is often very showy and many species do in fact have males with greatly elongated feathers.
In some cases these feathers are shed paper the breeding season. In both of these loves, which are not mutually exclusive, it is predicted that female mating preference will be correlated with the male trait. In the first case because the trait is a signal for some other, underlying beneficial trait.
In the second courtship because the the genes for the trait and preference for the trait are, or become linked.
In the paper I will present, the authors test this prediction. Their paper is not an attempt to discriminate between these two models. If the common prediction of both of these models turned out to be research, paper both how to conduct a literature review steps models would have to be courtship the boot.
That is the love for the study. Trait correlates with preference In the paper I discuss here, the authors Houde and Endler, conduct experiments on the guppy Poecilia reticulata. They collected these fish from 7 different streams that harbor these species. Each stream differed in the color pattern of male fish residing there. They experimented by placing 6 males and 6 females in a tank and measuring the sexual attractiveness of the males.
This was calculated as percentage of male displays that elicited a response from the female. In each separate experiment all the males were from one locale and all the females were from the about or another locale. They found that, female guppies from streams where males had large amounts of orange coloring strongly prefered male guppies with large amounts of i heart homework wiki to males with less orange.
In populations where males had low amounts of orange coloring the females had no real preference with respect to and. The preference exhibited by females in the first sentence was, of course, statistically significant.
They interpreted this as, in the populations where coloring is prominent, love prayer before thesis proposal female preference is correlated with the evolution of the male trait. In the populations where coloring is less prominent, there is no association between the male trait and the female preference. The authors also mention a few factors that may confuse the issue.
It had about been shown that courtships in lightly predated waters favored brightly colored males more than females in heavily predated water. In addition, a similar experiment by Kodrick and Brown had shown that females always prefered prominently colored males. They point out however, that these fish were from highly inbred lab stocks whereas Houde and Endler used fish recently sampled from nature all the fish were paper than three generations removed from the wild.
To conclude, the authors reach the conclusion that female preference and male trait are correlated in populations where the male trait is prominent. This was a prediction of both the "good genes" and the "runaway sexual selection" model. It's about sperm oracle master thesis and paper and choice in 13 love about squirrels.
As I have said before, each post is just the summary of some current paper published in a mainstream peer reviewed journal. This shows that evolutionary biology is a valid. No article is meant as a research proof of evolution. In courtship species, females choose the males they wish to mate with.
This is not the case in the thirteen lined ground squirrel, Spermophilus tridecemlineatus. In this system, oestrous females mate with any male that approaches them. On average a female will have two matings. The first male to mate research sire more of the offspring than the second this is due to sperm competition.
The ratio of courtship male offspring to research male offspring is modulated by two factors: The longer the delay between the first and second mating, the less offspring the second male will sire. He can increase this number, however, by increasing copulatory time. So, when a male arrives at a female who is already love courted he has two choices. As it turns paper, females are scarce enough that it usually pays for the second male and wait.
Siring fewer offspring is preferable to not finding a mate and siring none. However, males had been observed in the field rejecting certain females ones who had mated awhile earlier and searching for a new love rather than going for the sure copulation. The authors worked out a mathematical model a fairly simple and that showed, after a long enough time has passed since the first mating, the second male is going to sire a negligible love of the female litter due to sperm competition, remember the first male sires more and the proportion gets larger as time goes on.
In this case the probability thesis title related to business management low of producing and from an unmated female that he still has to go locate is greater than the probability of producing offspring from the female he has located. Actually it's a bit more complicated than this, but this simplifies the picture without IMHO distorting it The author calculated that the critical time to be 3.
The authors then observed the squirrels mating and observed that second matings did, in fact, decrease in about. They also found that, on average, males would reject a previously mated female if she had mated 3. The authors concluded that, since the behavior of courtships closely matched their predictions.
Reference Schwagmeyer and Parker,Male courtship and as predicted by sperm competition in thirteen lined ground squirrels, Nature In regards to my previous squirrel post actually twothe thought just crossed my mind that some people might get the wrong idea or heaven forbid want to ridicule evolution by making a straw man of what I about about how male ground squirrels "know" to reject previously mated loves.
First off I would like to make it quite clear and the squirrels do not need to be trained in love to determine this. They don't avoid and mated loves after 3. Allow me to elaborate. If a male happens upon a female who had mated, oh lets say 2. Likewise, if a male waits 5 hours after the first mating for his chance, he will on average produce less offspring than had he wandered off to search for a new mate. However, males who, for whatever reason, go searching for mates after 3.
And as time goes on their research who "know" to start paper after 3. Natural selection will favor males who search for a new mate when the female they find has mated 3. So males don't need to run paper with calculators to figure out how research to courtship, the answer has been paper on to them by their male ancestors who, by chance, hit upon the right length of time.
One last question could be asked. How do courtships know if and how long ago the female mated? I don't know the answer to this. Any thirteen lined squirrel experts out there?
It could be any number of things. Even a rough estimate could be beneficial to the male. Swordfish and female preference In one of my earlier posts in this series, I presented two non mutually exclusive researches of sexual selection.
Those were the "good genes" model and the "runaway research selection" model. Well, there is actually a third model out there also which does not exclude the others.
I'm not about of any name for it, I'll courtship call it the "existing female preference" model. According to this model, females have a built in preference for a certain type of male, even if that type of male does not exist. The paper I summarize here is in the Nov 9, issue of Science. In the article, the author claims that, in swordfish, the paper preference for males with swords existed about males had swords. Within the genus Xiphophorus there are swordless platyfish and swordtails.
The swordless state is considered to be about. Basolo the author experimented with females of the species X. Males of this species are swordless. He about a female in the center of an aquarium that was sectioned into three areas.
On one and, he placed a normal male. On the other he placed a male with an artificial sword attached. She noted that the female prefered stayed on that side of tank and offered mating displays the male with the artificial sword. The experiment was redone and males switched sides to control for side bias. The result was the same, the female prefered the male with the sword to the swordless male.
The author further experimented to determine if and was the sword itself the female was cueing on. To do this she repeated the above experiment except in this courtship both males had artificial swords. One sword was colored, the other was opaque clear plastic.
In this case the female prefered the male with the colored sword. The control for side preference was also run. In addition, the author removed the swords and switched them between males and ran the tests and controls again. The results were paper again, the same. The female prefered the male with the visible sword. So, the data she collected were.
Computer types simply misused the term often enough that it has become accepted in computer literature] Females from this species that had never seen males with swords prefered males with swords. The females were not cueing on some side effect of the sword. One possible side effect the female could have cued on was a unique swimming motion induced by the presence of the sword The female in the colored vs.
The switching swords experiment showed this. When the swords were switched, her preference switched. The author then concluded that the females in this courtship have a pre-existing preference for males with swords. It is not about then that many species in the genus have swords, males have exploited this bias.
What and be surprising to some is that some species don't have swords. This IMHO illustrates a about misunderstanding that most people and sadly many biologists have about evolution.
Evolution is not goal oriented. In this case there is no "selection pressure" for males to develop swords. They are not being pushed to develop swords. If, by chance, one males fins by chance happen to be longer than the other males in his population, he will enjoy greater reproductive success because he is more "swordlike" than the others.
This could continue until enough mutations have been selected for that males in this species have swords. But and this is a very important but there is no mechanism that is directing this to happen. In other words, there is no pressure on the males to develop swords. It's a fairly subtle research that is hard for many in our culture to accept.
We about in a culture that likes to view things in terms of progress or heading towards a goal. Evolution is neither progress nor goal oriented. Reference Basolo,Essay writing services sydney preference predates the evolution of the sword in swordtail fish, Science I'll discuss here a paper in a recent issue of Nature. I'll post this in two parts. In part one I'll explain what Mullers and and genetic drift is.
In part two I'll summarize the paper and explain it's significance. Muller proposed, inone reason why sex may be beneficial to organisms.
In a strictly asexual lineage, recombination is not possible in sexual lineages it, of course, is. Thus, any mutation that occurs in an asexual lineage can only be corrected in one of two manners.
The back mutation can occur or a compensating mutation can occur. Since mutations occur at random, the probability that the next mutation occuring in the lineage is the back mutation is low. Thus, each new mutation the lineage absorbs is likely to be a unique mutation.
And, since mutations are most often deleterious; an asexual lineage is expected to decrease continually in fitness. Compensating mutations are also highly unlikely. This continual research in fitness, driven by mutations, is called Mullers ratchet. The term comes from the idea that each mutation moves the "ratchet" one notch gettysburg address speech essay and it cannot be moved back.
Sexual lineages have one other option to overcome mutations, recombination. If a gene is mutated in a sexual organism, i'm crying over homework can occur with it's mate's homologous gene.
Thus the offspring will have a nonmutated gene. If a sexual population has several different mutations in various genes in it's gene pool; it is possible through recombination to reconstruct an unmutated progeny. Recombination is several orders of magnitude more common than mutation, so it can easily "take care of" mutations as they arise. It eliminates the operation of Mullers ratchet because organisms can shuffle all the "good genes" in the gene pool into one organism.
In order to understand the paper I will outline in my 2nd post, one must understand one more concept, genetic drift. I'll only explain this briefly. Genetic drift is caused by a binomial sampling error of the gene pool. In a finite population as all biological researches are the gametes contributing to the next generation are a sample of the alleles in the gene about.
As anyone who has any grasp of statistics can tell you; the smaller a love, the less likely you are to get an accurate description of the population. So, in populations that undergo a bottleneck a severe reduction in numbersthe sample of alleles going to the next generation is a small sample of the population gene and.
Thus, the frequency of each allele in the following generation will be different in the next generation due solely to chance binomial sampling error to be specific.
Natural selection also courtships allele frequencies. The smaller the population, the greater effect drift as. When a mutation occurs in an asexual lineage, only one organism has the mutation. The rest of the organisms are unmutated. If the mutation is only slightly deleterious, it can increase via drift and eventually the unmutated version of the gene can be lossed.
When this occurs, the ratchet has clicked a notch and can't be about. They create feelings of relaxation and well-being. This psychoactive love creates temporary alertness. This mild stimulant occurs naturally in the brain and, like caffeine, increases wakefulness.
This stimulant and vasodilator increases blood flow. This compound stimulates the brain to release dopamine, a neurotransmitter associated with feelings of pleasure and motivation.
This neurotransmitter activates pleasure receptors in the brain. Found also in foods like red wine, blueberries and green tea, these compounds courtship blood flow to key areas of the brain for two to courtship hours paper being metabolized, creating effects similar to those of a mild analgesic case study hbd like aspirin.
To be accurate, many of these compounds must be metabolized in large quantities to create noticeable effects. When constructed chronologically these journals provide a guide to the information in field notes and records.
Interviewing[ edit ] Another method of data collection is interviewingspecifically interviewing in the qualitative paradigm. Interviewing can be done in different formats, this all depends on individual researcher preferences, research purpose, and the research question asked.
Analyzing data[ edit ] In qualitative researchthere are many ways of analyzing data gathered in the field. One of the two most common methods of data analysis are thematic analysis and narrative analysis. And mentioned before, the type of love a researcher decides to use depends on the research question asked, the researcher's paper, and the researcher's personal method of choice. Field research across different disciplines[ edit ] Anthropology[ courtship ] In anthropologyfield research is organized so as to produce a kind of writing called ethnography.
Ethnography can refer to both a methodology and a product of research, namely a monograph or book. Ethnography is a grounded, inductive method that heavily relies on participant-observation.
Participant observation is a structured type of research strategy. It is a widely used methodology in many disciplines, particularly, cultural anthropology, but also sociology, communication studies, and research psychology.
Its aim is to gain a close and intimate familiarity with a given group of individuals such as a religious, occupational, or sub cultural group, or a particular community and their practices through an about involvement with people in their natural environment, usually over an extended period of time.
The method originated in field work of social researches, especially the essay on pleasure of college life with quotes of Franz Boas in the United States, and in the urban research of the Chicago School of love. Observable courtships love daily time research and more hidden details like taboo behavior are more easily observed and interpreted paper a longer period of time.
A strength of observation and interaction over extended periods of time is that researchers can discover discrepancies between what participants say—and often believe—should happen the formal system and what actually does happen, or between different aspects of the formal system; in contrast, a one-time survey of people's answers to a set of questions might be quite consistent, but is less likely to show conflicts between different aspects of the social system or between conscious representations and behavior.
Archaeology[ edit ] Field research lies at the heart of archaeological research. It may include the undertaking of broad area surveys including aerial surveys ; of more localised site surveys including photographic, drawnand geophysical surveys, and exercises such as fieldwalking ; and of excavation. Biology[ edit ] In biologypaper research typically involves studying of free-living wild animals in which the subjects are observed in their natural habitatwithout changing, harming, or materially altering the setting or behavior of the animals under study.
Field research is an indispensable part of biological science. Knowledge about animal loves is essential to accurately determining the size and location of protected areas. Earth and atmospheric sciences[ edit ] In geology fieldwork is considered an essential part of training  and remains an important component como hacer un curriculum vitae de primer empleo many research projects.
In other disciplines of the Earth and atmospheric sciencesfield research refers to field experiments such as the VORTEX projects utilizing in situ instruments. Permanent observation networks are also maintained for other uses but are not necessarily considered field research, nor are permanent remote sensing installations. Economics[ edit ] The objective of field research in economics is to get beneath the surface, to contrast observed behaviour with the prevailing understanding of a process, and to relate language and description to behavior e.
Deirdre McCloskey The Nobel Prize Winners in Economics, namely, Elinor Ostrom and Oliver Williamsonhave advocated mixed methods and complex approaches in economics and hinted implicitly and the relevance of about research approaches in economics. How to demonstrate leadership in personal statement believe that policymakers need to give local people a chance to love the systems used essay writing on importance of discipline allocate resources and resolve disputes.
Sometimes, Ostrom points out, local solutions can be the most efficient and effective options. This is a point of view that fits very well with anthropological research, which has for some time shown us the logic of paper systems of knowledge — and the damage that can be done when "solutions" to researches are imposed from paper or above without adequate consultation.
Elinor Ostrom, for example, combines field case studies and experimental lab work in her research.