Jenna's Evolution Blog (BIOL 540)

The disease I would like to discuss is Clostiodioides difficile, commonly referred to as C. diff. It is an infection of the gut that causes extreme colitis and diarrhea, as well as nausea, fever, and stomach discomfort. It most commonly occurs in patients after taking antibiotics for an extended period of time or in a particularly high dose--it is also common for patients that have had a stay in the hospital (known as an iatrogenic infection) to get C. diff since it is so incredibly contagious and people with it often have to go to the hospital. I thought this would be an interesting disease to cover because not only is it often overlooked as a deadly, miserable, and very common disease, but it also has roots in the overuse of antibiotics that western medicine has been guilty of for years. Another element of this is without a doubt a western lifestyle (sedentary and unhealthy eating) ignoring the huge role that diet plays into gut health in the microbiome. Both of these play a big part...

Speciation is something that comes usually from a buildup of mutations between at least a couple of generations. Since separate species have to have exclusive mating within their populations, it takes a lot of gradual buildup of mutations to branch off from one species to another. It especially would take even longer for the change in mutations to be so great that even when living in the same geographic area, they still managed to diverge into different species. I can see however that in the case of allopatric speciation, how it could happen faster than sympatric. Since the two groups would be in different environments, similar to what we see in Darwin's finches, it is more likely we would begin to see different mutations between the different groups. Obviously it takes a lot more mutations than that to create a whole new species, but it's essentially the same mechanism. Of course, it does depend on the species and the overall mutations rate of the organism. Every species is di...

 I think when it comes to sexual dimorphism and who courts who, the most important thing to remember is that in reality--it's not about sex of the individuals involved at all. As we discussed in class, it's about who invests more into the offspring instead! In probably 99% of species on earth, it is the case that females of a population are the ones that "invest more" into the offspring because they are the ones who are pregnant, give birth, breastfeed, do more of the early life care, etc. In the case of pipefish, however, it is the males who carry the babies inside them into they are ready to make their grand entrance! It makes perfect sense when you think about it that this courting phenomenon takes place--since procreating is so much work for the sex carrying the babies, they want to be woo-ed into choosing the best possible mate. They aren't going to go through that for just anybody--they're going to need to see some showgirl-like fin action before they co...

Blobfish: The Original "No Bones" Day Animal The Blobfish is an animal most of us may have seen in a meme or otherwise before because they are continuously regarded and one of the ugliest animals to ever exist. Photo evidence appears above. The reason Blobfish look like...that... is because they live extremely close to the ocean floor, between 2000 and 4000 feet below sea level depending on the area. This puts them living at a pressure between 60 and 120 times larger than sea level. To put this into perspective, here is this quote from an article on Australia's Science Channel: " There is so much pressure at that depth a human would feel as if a passenger aircraft was parked on top of them". Another fun fact: these fish don't look entirely this awful in their natural habitat--it's because the pressure on land is so much lower that they start to look like this pile of snot. It takes a lot of interesting adaptation to be able to live in these conditions ne...

If I'm not mistaken, one of the biggest reasons like genetic variation is not eroded over time is because of new mutations arising to create changes in populations. Some of these mutations may be good or bad, and OFTEN (not necessarily always), the bad mutations will be selected against and will go down in frequency. But as we discussed in one of our past classes, if the mutation is in a recessive allele, it will never completely go away as it can be hidden by heterozygote phenotypes, resulting in eventual offspring with the homozygous recessive mutation yet again. Selection doesn't work against heterozygotes here because they present the same as homozygous dominant individuals. In terms of advantageous mutations, it's a little more obvious that these mutations will not go away and will again create genetic diversity that will not be selected against. 

     It has been so incredibly relieving to be able to sit through a lecture and really LISTEN to what is being said and participate while occasionally  writing down notes, compared to other classes where I am constantly scrambling to write things down so I hardly even hear what my professor says. I feel like I am much more involved in the lecture and I'm really learning from it because I'm not just trying to cram in information so I can do well on a test. ALSO: I consider myself to be quite computer-illiterate. I would never think I would be able to put together pieces of code to make graphs and do such cool functions--it makes me really happy and proud of myself because I'm doing something I probably never would have done if it weren't for taking this class.           I would say my first definition of evolution was pretty decent, just the basics of heritable traits changing over multiple generations in a population. However, something...