Directed Reading 13.1 Section: The Theory of Evolution by Natural Selection In the space provided, write the letter of the term or phrase that best completes each statement or best answers each question. ______ 1. Some individuals of a population or species are better suited to a. evolve than other individuals. b. survive and reproduce. c. become extinct.
The Aztec and Mayan Civilizations in the Americas Ashley M. Carpenter Western Civilization II National University June 2, 2012 Abstract From 250 A.D. to the late 1500’s A.D. the Mayans and the Aztecs controlled Central and South America. Each was unique, but still shared a few of the same traits. Both had their own calendar system, counting system, and Polytheistic religious beliefs along with similar temples built to worship their deities. While the Aztecs were the most prominent users of human sacrifice, the Mayans also participated in such rituals. A few differences between these civilizations were the social structure, natural resources, and differing cultural strengths.
Decreased variation leads to a reduced ability to respond to a changing environment. Darwin developed three kinds of theory of natural selection. Those are struggle for existence, variation and role of the environment. Survive of the fittest is the result of differences in rates of survival and reproduction. Darwin reasoned that natural selection could eventually cause isolated populations of the same species to becme separate species as they adopted to their different enviroments.
He discovered that the individuals who can survive long enough to procreate did so because of specific traits that had made them stronger and more able to survive than the ones that died off. This is known as “survival of the fittest.” Over time, the strong traits get passed down from generation to generation and the weak traits slowly disappear. Biology has shown that there are certain traits that get passed down genetically, for example, the Galapagos finches’ beak shape. The Galapagos finches developed different beak shapes depending on the type of food that was available in their environment. There was one group of finches that had narrow beaks for picking up seeds and insects, and another group that had shorter, stronger beaks for cracking nuts.
The extinct genus Miracinonyx was extremely cheetah-like, but recent DNA analysis has shown that Miracinonyx inexpectatus, Miracinonyx studeri, and Miracinonyx trumani (early to late Pleistocene epoch), found in North America and called the "North American cheetah" are not true cheetahs, instead being close relatives to the cougar. Subspecies Although many sources list six or more subspecies of cheetah, the taxonomic status of most of these subspecies is unresolved. [according to whom?] Acinonyx rex—the king cheetah—was abandoned as a subspecies after it was discovered that the variation was caused by a single recessive gene. The subspecies Acinonyx jubatus guttatus, the woolly cheetah, may also have been a variation due to a recessive gene.
I’m sure my ideas and goals would be completely different I wouldn’t be going to school to become a nurse I would be out in the land trying to hunt and gather. It’s hard to see myself killing an animal I could never do that now. Same in the agricultural society maybe my values wouldn’t change but I could see my goals and ideas being different. If this was the environment around me I would want to be doing well. 2.
How can we prioritise species for conservation? Species becoming extinct: Species are facing various problems key to their survival such as destruction of animal habitats, damage to the natural environment of living things, for example trees are cut down to build homes, , Oil spills, acid rain and water pollution also add to the destruction of habitats. Moreover another cause for extinction is when animals are over-hunted for their meat, fur and other valuable parts. Another cause could be ‘when animals or plants arrive into a new habitat from a foreign place they sometimes introduce diseases that the native species can't fight. These "exotic" species can also prey on the native species’.
Some animals are pulled out of their habitat and are used as research; yet some humans think they do not deserve any rights because they are animals. Throughout this paper I will portray examples of possibilities that can be used to change the life of an animal in the food industry, as a pet in homes and as research in laboratories; we need to help them have a better life even if we are going to use them as food, a companion and even as a science experiment, they have the right to enjoy life even if it’s for a moment. Factory farms today, thousands of animals are crammed into filthy, windowless sheds and confined to wire cages, gestation crates, barren dirt lots, and other cruel confinement systems. The factory farming industry strives to maximize output while minimizing costs of course at the animals' expense. The giant corporations that run most factory farms have found that they can make more money by cramming animals into tiny spaces, even though many of the animals get sick and some die.
The quality of the experiments was necessitous. In this study, Roberts (2007) states that, The anatomic, metabolic, and cellular differences between animals and people make animals poor models for human beings. Drugs that pass in animal test are not successful in human clinical tests. Animals as their matter are not germane to human health. Several can cause human diseases that can damage us instead of helping us.
People have yet to realize that their favorite type of deodorant or those good-smelling fragrances they like to put on were once tested on animals. These animals are forced to swallow or inhale large quantities of a test substance or endure the pain of having chemicals applied to their sensitive eyes and skin (Peta). Many times the results of animal tests are often not applicable to humans, but even if a product has blinded an animal, it can still be marketed to you. Many testing centers keep such animals out of their natural surroundings, until time to experiment on them. Throughout that time these animals become so unadapt to their new surroundings, they become less likely to return to their natural state which gives those experimenting more reason to test them.