Entry #9: Evolution and Medicine

I believe that medicine does need an evolutionary perspective. Modern medicine does not have to fully revolve around evolution, but adding it into the medicine field for doctors to better help people may be a good way to give people better treatment. How medicine could somehow have an evolutionary perspective is by doctors learning more about it. I know not many people are for evolution but it does help to explain many things in the science field. I think that if doctors did learn how the body evolved, it could help them in their practices. Just like a mechanic fixing a car, he needs to know everything about that part in order to fix it properly. If you know nothing about what you are trying to fix then you will fail. You need to learn background information first and then work your way up. Learning about the simpler facts and then moving up into the harder information is a good way to start off. If doctors learned about the basic body parts and worked their way inward into the harder organs and bones and how they evolved, it may help them to work with their patients better. Suppose a doctor is prescribing a type of medication, there are many different aspects they need to look at such as allergic reactions and side effects. If they somehow incorporate how the body first started off maybe they can be more careful in diagnosing and prescribing medications. So, I do believe that knowing how the body evolved would be a great benefit to doctors. Knowing more about the body may lessen the time it takes them to diagnose a patient.

Entry #8: Bipedality and Brain Size

The forces of natural selection that have come to make bipedality are seen to have come from African-ape behaviors that include every day living things such as feeding postures, mating displays and vertical climbing. They also say that it has evolved from chimpanzee like ancestors. One of the main structures that led to bipedality was the big toe, the strong thigh muscles and the strong hips. Organisms then needed to start using their upper bodies to carry things and do other sorts of activities. Being on both legs and upright helped organisms to do activities much easier such as movement. What led to the evolution of larger brain size than our primate ancestor is one of the factors that have affected us is climate. Some scientists think that our brain has become larger because we were thinking ahead of the climate changes that were going to happen so we had to learn to adapt. Another reason our brain may have become larger is because we migrated farther away from the equator and our brain became larger in order to become cleverer and figure more things out. Another factor deals with parasites. Our brain may have become larger in order to fight off parasites. One last factor was the fact that we all had to fight for resources. The more we had to fight for resources, the smarter we had to become in order to outsmart the others.

Entry #7: The Ancestor's Tale Ch 1-2

In Chapter 1 of the Ancestor’s Tale, the two misconceptions that Dawkins tells us to try and avoid are one that historians try to go back and “scour the past for patterns that repeat themselves.” According to Mark Twain they want to “seek reason and rhyme for everything.” The next one has to do with the present. Dawkins says that evolution is not something to repeat but something that rhymes. The second misconception away from the past and present is the conceit of hindsight. According to Dawkins. The conceit of hindsight is “the idea that the past works to deliver our particular present.” Dawkins talks about the different theories and the physicists that brings about how our universe was made and how it was brought about to produce humanity. How scientists determine the timing and the human migration out of Africa is by exploring family trees instead of family genes. What Y-chromosome Adam and mtDNA Eve tells us about human origins is that they are only one set of MRCA’s, there are many more. Second, they were not even together. Third, they are shifting titles and fourth there was no information to single either one of them out. This means that they did have multiple partners but Adam went down the male line and Eve went down the female line. This may not be the rue story because Dawkins even said that relying on a single gene could be misleading and there are many more factors that can be added into how our human origins came about.

Entry #6: Evolution Of Altruism

There are many different ways in which altruism can evolve. Like we saw in the movie about the meerkats, there were babysitters that stayed behind and watched other female meerkats babies. The babysitters did not have to do this, but they did this in order to benefit themselves and hopefully in return they will also get something back. Reproductive altruism is a type of altruism where the individual does something to enhance the reproduction of another individual even if it is a cost to its own fitness. An example of this would be wolfs hunting in a pack. The wolves need to cooperate together in order to bring down a larger animal or possibly hunt down something tastier and more meaty. While doing this the wolves are increasing their fitness. With the vampire bat scenario, the bats that go out and hunt and find blood may sometimes share with other neighboring bats. This is crucial that a vampire bat gets something to eat because if they don’t they will die. If a vampire bat cannot find anything to eat, they will rely on their fellow bats to share with them. The bat that does end up sharing his food with other bats will expect all of them to return the favor at some point if there is one time where he cannot get food himself. This can be a safe cushion for the bat so hopefully other bats will remember what he did for them. If so the vampire bat may be able to find a fellow vampire bat that he can trust and they can work in pairs and possibly rotate and choose each night who will share and who will go out and hunt.

Entry #5: Queen Bees and Workers

The conflict that is between queen and worker bees is that the queen is the one that gets to lay the eggs and pass on her genes and the worker bees do not get to. They way in which it is decided if you are going to be a worker bee or a queen bee, is by what you are fed. If you are fed royal jelly you will become a queen bee. Between the worker bee and the queen bee, the queen bee always ends up winning. There are some worker bees that try to get away with laying their own eggs in the hive but those eggs end up getting removed. Other worker bees in the hive may remove the eggs that were laid by another worker bee. Indication of a different scent or the position of the egg may give it away that the egg laid is not that of the queen bee. There are some exceptions that can occur. Sometimes a worker bee can become a layering worker bee. This bee is a worker bee but it can lay eggs safely in the absence of a proper queen bee, although some other worker bees may also remove them if they are not recognized. A layering bee usually develops a couple of weeks after a queen bee has been absent. When a queen is absent the layering bee may lay eggs, but these eggs only give rise to drones. Besides a layering bee, it is almost always only the queen that may lay eggs and successfully produce offspring.

Entry #4: Natural and Sexual Selection

Natural selection is an evolutionary process where organisms inherit heritable traits that help them to live longer lives. These traits can help the organism live a longer life and also help the generations after them and their offspring survive and keep the lineage prolonged. Sexual selection is the struggle between individuals of one sex in order to have possession over the other sex. How Darwin explains the difference between the two is that natural selection is the “struggle for existence in relation to other organic beings or to external conditions” and that sexual selection is the “struggle between the individuals of one sex, generally the males, for the possession of the other sex.” How Dawkins explains the difference between the two is he calls natural selection “Parental Investment” which is “any investment by the parent in an individual offspring that increases the offspring’s chance of surviving at the cost of the parent’s ability to invest in other offspring.” He looks at sexual selection as being a battle of the sexes. Both sexes want sons and daughters in equal numbers, and with this they agree. With what they disagree with is who is going to “bear the brunt of the cost of rearing each one of those children.” Darwin says that they do want children but who is going to put more effort into raising them, the mother or the father? The mother and the father want their children to survive but they need to invest energy into bringing them up.

Entry #3: Sex Ratios and ESS

The ESS concept stands for Evolutionarily Stable Strategy. Dawkin states that this type of strategy is a strategy that if most members of a population adopt it, cannot be bettered by an alternative strategy. The reason Fisher stated that a sex ratio of 50:50 (males:females) is an ESS is because he said that it will counter any bias. If there was a gene that was bias towards a certain sex, then the others would have lower mating success just as Fisher states. But, selection will go in the other sexes favor, making sure the ratio will stay balanced again. I believe that the autosomal chromosomes and the sex chromosomes will both favor a 50:50 ratio. Both males and females need the autosomes and the sex chromosomes to become a full human being. The autosomes are the first 22 pairs, which both males and females need so there is no competition needed, and the sex chromosomes which is the 23rd pair, is needed in both males and females. The only difference is the sex chromosomes determines the sex of the male or female. The only competition here is whether or not the chromosome will be XY or XX. The cytoplasmic elements are not a 50:50 ratio. Some elements are used more than others, but this cannot be helped since every element has a certain job it must do. Such as the mitochondria which makes ATP, it will not compete with the endoplasmic reticulum because it has no reason to take its job. The chromosomes are different from the cytoplasmic elements in that they determine the make up of a human being and the cytoplasmic elements help to keep them running. Therefore there is no reason for the cytoplasmic elements to counter each other if the ratio is not always 50:50.

Entry #2: Major Transitions in Evolution

Mayhew proposed that sex was a major transition and so he goes into the whole process of meiosis and the way it works. He also talks about autotrophic and heterotrophic origins of the biosphere. Dawkins proposed and talks about DNA and replicators that competed for these 'building blocks'. He then proposes that the replicators that survived are the ones that made 'survival machines' to live in. These survival machines are what multicellular organisms are. Both Dawkins and Mayhew talk about DNA and they both talk about the way an organism is made up when two organisms have sex and the process that takes place internally on a molecular level. The differences between these two is that Mayhew talks about recombination and the different processes that may have favored it and he also talks about mutations that can occur which affects the genes of an organism. The scenario that is most likely when choosing between the heterotrophic and autotrophic theories on the origin of life is the autotrophic theory. The autotrophic theory makes more sense on a scientific level and seems like there was more thought put into how replicators became multicellular organisms. The fact that the autotrophic theory has many reasons for why it had taken place also makes it a better and more believable theory rather than the heterotrophic theory. It can be very so that a prokaryotic cell had lost its cell wall in order to engulf large organic particles.

Entry #1: Domestication

The problems with this argument that Darwin identified is he says that domestic species are not different when it comes to their genes. This could not be true because many of the domesticated species of today look nothing alike. There are now many different types of breed of dog. They may have all come from one specific type of dog but the genes have changed as more and more different species were bred. Darwin also says that some races have been modified by other different crosses. I believe that the domestication process may have started out with just one type of species of dog but grew as more and more different species were discovered.
On a genetic level, you could look at the different variation of the genes and the genetic make up of the animals. A mutation, which is a rare gene that is inherited could also cause the different breeds of dogs that we have today. Many of the crosses between the different types of dogs could somewhere in between contain a mutation. Another reason could be because of epistasis which is where a gene influences the expression of another genes phenotype.
Dawkins says that the "survival of the fittest" is an organism that will sacrifice itself when needed to save the species as a whole. He is implying that the species that are not being selfish will survive.
Ecology plays a role in the domestication of the dog because the dogs that were isolated from the wild dogs may have been easier to domesticate.