BIOLOGICAL EVOLUTION notes

BIOLOGICAL EVOLUTION notes - BIOLOGICAL EVOLUTION...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: BIOLOGICAL EVOLUTION Historically: Before 1750 --> - supported by the Judeo-Christian belief in the Old Testament book of Genesis Late 18th Century Georges Cuvier tried to explain changes seen in fossils found in successive soil layers: -- changes in species resulted from catastrophies, which wiped out local species. New species moved in from surrounding areas. 1809 Lamarck --> - all existing species are descended from other species. Lamarcks theory: Inheritance of Acquired Characteristics Ex: Giraffes and their long necks evolved from ancestors who increased neck length by stretching to feed on higher branches 1858 Charles Darwin and Alfred Russel Wallace Mechanism proposed for evolution: Darwin studied variations among finches and tortoises on the Galapagos Islands. Darwin's theory sometimes referred to as survival of the fittest -- meaning survival of the fittest phenotype for the prevailing environmental conditions .- those individuals producing the greatest number of viable offspring are said to be the most fit . Biological Evolution - an ongoing process of change in the genetic makeup of a species over time. These changes represent adaptations to the organisms environment. Organisms change over time -- modified from pre-existing forms (ancestors). Biological evolution is driven by the process called Natural Selection. It is important to note that but this ultimately selects the most favorable genotype. Evidence for Evolution 1.) Artificial Selection Controlled breeding of selected domestic plants and animals. Ex: dairy cows, corn hybrids, dogs, flowers.--> demonstrated that organisms can evolve. 2.) Evidence from the fossil record fossil = preserved evidence of past life. a. most fossils found are of extinct species b. some species are older than others --> deeper rock layers have older fossils c. d. -- birds, mammals, horse 3. Evidence from comparative anatomy - compare body structure of species alive today Ex: forelimb bones mammals, birds, reptiles and adult amphibians all have forelimbs with the same basic framework....
View Full Document

Page1 / 28

BIOLOGICAL EVOLUTION notes - BIOLOGICAL EVOLUTION...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online