Megan McCoy

A trait on an animal that has always fascinated me is the pouch on a kangaroo. I always thought it was more like a pocket on the outside of the kangaroos stomach, but it looks and seems a whole lot more intricate than that. It is a fold on the skin that is exclusive to females. The pouch is hairless on the inside and allows the offspring to feed off the mother's milk. The pouch covers their breasts, and due to this it forms an epidermal bag which takes the role of an incubator. This is an adaptation that enables the offspring to be cared for at different stages of their life/development. They use this pouch to carry their babies and nurse them while still being quite mobile. Something that was very new to me was that the inside lining of the pouch is lined with sweat glands that release antimicrobial liquid. This is to ensure the health and safety of the offspring. 

The definition of genetic variation is the difference in the sequence of genes between the individuals and organisms in a species. We also see that natural selection is the process where organisms that are better suited for the environment they live in tend to survive and produce more offspring. In a sense, genetic variation drives natural selection. Natural selection would not be possible without a genetic difference in genes within a population.  There is a clear answer as to why natural selection has not eroded genetic variation over time, and the answer is mutations. If natural selection has taken place within a population, that does not stop the fact that mutations will still take place. This creates a whole new genetic variation amongst the population over generations. It creates a new gene pool and starts the process all over again. Mutations occur and they could be for the better of the population. In this case natural selection will take place and create a population ...

     Coming into this class I definitely was not expecting to code or learn in this sort of way. It made me really nervous because as a biology major, I have never had to even look at code before. At the beginning I definitely struggled with the R exercises, but I feel as the weeks go on I get more comfortable using Rstudio. Although I don't feel as intimidated by R anymore, I still have questions about certain codes on our exercises. It is definitely a challenge, but it is a new way of learning for me.      Looking back on my first blog post, I related evolution to adaptation and natural selection. Although that response isn't necessarily wrong, I now know it is much more intricate and deeper than that. I basically thought that evolution and natural selection were the same thing, but now I understand that natural selection drives evolution to take place. There are many working parts in order for evolution to occur and one that fascinates me the m...

Inbreeding:       Inbreeding is the production of offspring from the breeding of individuals that are genetically closely related to one another. According to the internet, it says that assortative mating is where individuals with similar genetic makeup mate with each other more frequently than a random mating pattern. A benefit of inbreeding could be in the circumstance where two organisms are both genetically fit for its own environment and thrive under those circumstances. Those two organisms can mate, and create an offspring that has a great overall fitness to survive in that habitat as well. This could create a larger population.      Inbreeding also has some negative effects as well. Disassortative mating is a pattern in which individuals with very different phenotypes mate with one another more frequently than random mating. This reduces the genetic similarities in a population and produces more heterozygotes. Some of the negative effects t...

Before having any biology classes, I would have thought of fitness as working out and staying in shape. If someone had great fitness, that just meant to me that they were in great shape. But now after having many years of biology, I know the second meaning of fitness relating to the evolution/biology aspects. In simple terms, fitness in evolution means reproductive success and how well an organism adapts to its environment. If the species is no longer reproducing, that means they are no longer evolutionary fit. To measure fitness in a natural population, you would measure the organism's ability to create offspring. This determine the amount of genetic material the organism has contributed to the population and next generation. Some organisms are more fit than other depending on the environment and habitat they live in. When I think of fitness, I begin to think about the organisms that have gone extinct. One that comes to mind is the Woolly Mammoth. This organism was once fit for it...

Microevolution is something that was easier for me to understand and follow compared to the other ideas from Darwin. Microevolution is the evolutionary change within a species over a short amount of time. I think microevolution relates to natural selection in the sense that natural selections drives the changes within the species that shows the differences over the shorter period of time. Microevolution can take place over one generation, where macroevolution takes place over a much longer period of time.  I researched about the various sparrow sizes throughout the United States to see what differences there were and how that related to microevolution. By taking a quick glance at the picture I attached above, it is apparent that sparrows have evolved different characteristics depending on their environment and location. We see that on the west coast, sparrows are a lot smaller in size compared to the ones up north and east. Sparrow populations that are bigger up north are due to na...

When I think of evolution the first thing that comes to mind is adaptation. Growing up and learning about evolution I never fully understood 100% what it was or how it was determined. I always thought that it was very similar to natural selection, but I now know that is not the case. It seems as if natural selection drives the events of evolution. I think the perfect definition of evolution is the changing of genetics to adapt to an environment over time. I think evolution is unclear to many people including myself because it is a very long and invisible process. I am a very visual learner and that is why it is harder to understand. Evolution is also not just one thing, it is an assortment of many different parts that makes it harder to understand. Something that came up in class was evolution being described as survival of the fittest. This to me doesn't necessarily mean the biggest, more muscular, fastest organism will survive. I have learned that survival of the fittest relates ...