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This week wasn't particularly stressful; I didn't really have trouble with anything in class and understood everything fairly well. We got our assignment to campaign for a specific piece of evidence that supports evolution. My group is doing embryology. It seems like a lot of work, but it's also interesting, and the competitive aspect is certainly a good motivator. I can't help but wish I'd gotten DNA or fossil records instead, though. I'm more familiar with those than with embryology, so I'll have to conduct more research. Our first FRQ is coming up soon; I'm not worried about it, but I certainly don't think I can just breeze through it either.

Chapter 6

Chapter 6 is all about human evolution. I thought this chapter was very gripping; seeing how things that we take for granted (like bipedalism and the ability to touch our thumb with our pinky) have had such huge effect on the course of our evolution was fascinating. It's very strange to think that something as small as that is the reason why humanity is where it is today. There are some things I'm a bit confused about; the chapter talks about increased protein consumption fueling brain growth, but I don't understand how this would have been passed down and proliferated throughout the species. 

Chapter 5

Chapter 5 is about adaptations. It explains things like constraints (adaptations limiting the environments in which an organism can survive (ex: icefish)), pleiotropy (one gene influencing multiple phenotypic traits), and vestigial structures. A lot of this was information that I had a vague idea of, but this chapter elaborated on it and gave examples. It's interesting to see how these concepts apply to the real world.

Chapter 4

The main topic in chapter 4 is speciation. The chapter defines speciation, provides examples for its possible causes and results, and also goes over sexual selection and its advantages. The chapter ends with a few pages about hybrids. I thought this chapter was pretty funny; the picture of the avenue bower bird actually made me laugh out loud. This was mostly review for me, but it's still entertaining.I don't really have any questions about this chapter.

Chapter 3

Chapter 3 goes over the five main extinction events, the progress of evolution from the Permian to the Triassic, and then explains background extinction and its causes. This chapter had some new information that was new to me; for example, I had no idea what a moa was, or how New Zealand used to be dominated by massive birds. It was surprisingly fascinating; not so long ago, creatures that sound more like something out a video game than actual animals roamed the lands where the Lord of the Rings trilogy was shot. Then, as humanity is wont to do, we promptly devastated their habitat and hunted them to near extinction-but so it goes. Survival of the fittest and all that. An Edgar Allan Poe reference caught me by surprise, and made me chuckle. This chapter also introduced a conflict to the plot; apparently, the "Squinches" are facing some sort of genetic crisis. I'm interested to see how this develops. 

Chapter 2

Chapter 2 summarizes the different evolutionary radiations that took place from the Cambrian to the Permian period, and ends in a cliffhanger as the supercontinent of Pangaea is formed. Personally, I was glad to see that this was all new information to me; we never went over this last year in honors bio. It was actually surprisingly interesting, too. Seeing how life has evolved throughout earth's multi-billion year history really gives you a sense of wonder and insignificance. To give you an idea of how little time we've really been here, the first hominids appeared around 2.5 million years ago, Homo Sapiens appeared 500,000 years ago, and civilization only started around 10,000 years ago with the agricultural revolutions. It's amazing to think of what humanity has achieved as a species, considering the (relatively) short amount of time we've been here. 

Chapter 1 Review

The first chapter begins with an explanation of when the chemical precursors for life may have begun to form. It then explains the proteins are the molecules that perform essential life functions, and elaborates on how the order of amino acids determines a proteins function. After the prince inquires as to how the cell know which amino acids to connect to create a protein, the scientist explains that DNA is the key; enzymes read DNA to produce RNA, which is then decoded by a ribosome to produce the amino acids in the proper order. Afterwards, Miller and Urey's experiment of early earth conditions and the generation of amino acids and nucleotides (the building blocks of DNA/RNA) is shown. Next, the evolution from ribozymes to archae, eukaryotes, and bacteria is explained, and the initial dominance and eventual decline of bacteria is mentioned. Finally,  the evolution of eukaryotes into multi-cellular organisms, and the formation of fungi, plants, and animals is shown. Having a visual representation really helps me realize just how far evolution has come; this is much more entertaining than reading from a textbook.