The story of the human body evolution health and disease sparknotes

For example, it caused our spines to curve and shortened our legs. However, there were some drawbacks as well. Thus, we can see that walking upright was advantageous for humans. In fact, chimpanzees are twice as fast and strong as humans despite being much smaller than we are! However, it came at a costвЂ“we lost other abilities that chimpanzees have, such as strength and speed. ThatвЂ™s what made us so successful as a species. Our evolutionary path began when our ancestors stopped crawling around and started walking upright. Humans are the dominant species on earth. It came with both costs and one big advantage. Big Idea #2: Walking upright made humans what they are. In the following key points, weвЂ™ll explore how it applies to human history. In this passage, the author summarizes DarwinвЂ™s theory of evolution. These help both the original organism and its offspring thrive in times of dramatic environmental change such as climate change. Environmental changes cause natural selection to use a different tool вЂ“ adaption, which describes how an individual develops new heritable traits that help it adapt to new surroundings. Organisms without significant new heritable traits come out on top.Д«iological processes are essentially biological. It would rather leave things as they are than change them. Negative selection is a process that favors the current situation. This explains why people with hemophilia have fewer children than others since they canвЂ™t reproduce easily themselves and need medical assistance to do so. If an organism has a negative trait, itвЂ™s less likely to survive than organisms without those traits. These are bad things that lower the chance of survival, such as hemophilia in humans.

Natural selection is usually driven by negative traits. Different species will vary in their reproductive success, meaning that some species will produce more offspring than others. Genetics plays a role in the growth of organisms. First, there is variability among individual organisms within the same species.

The theory of natural selection can be divided into three parts. This means the best-adapted members of a species survive and reproduce, while their weaker counterparts die off. It was a book that challenged religious beliefs and shook up centuries of thinking about how humans came to be.Дarwin believed that evolution was driven by natural selection. Big Idea #1: Evolution works according to the logic of natural selection and adaptation.Д¬harles Darwin published On the Origin of Species in 1859. Finally, you will discover why the birth of agriculture was both a blessing and a curse. YouвЂ™ll also learn why posture can shape the fortunes of an entire species. In this passage, youвЂ™ll learn about how natural selection interacts with environmental changes.

The story of the human body evolution health and disease sparknotes