Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
The Selfish Gene wikipedia , lookup
Evolution of ageing wikipedia , lookup
Saltation (biology) wikipedia , lookup
Co-operation (evolution) wikipedia , lookup
Population genetics wikipedia , lookup
Hologenome theory of evolution wikipedia , lookup
Genetics and the Origin of Species wikipedia , lookup
The Descent of Man, and Selection in Relation to Sex wikipedia , lookup
Sexual selection wikipedia , lookup
13.1 Ecologists Study Relationships Agenda – 04.29.2015 1. 2. 3. 4. Warm-up 10.3 Reading Preview and Bioterms 10.3 Notes The Making of the Fittest 10.3 Theory of Natural Selection Warm - up • Tell me what you know about Natural Selection When you are done start working on 10.3 reading preview 10.3 Theory of Natural Selection OBJECTIVES • Compare artificial selection to natural selection • Examine the factors Darwin considered in forming his theory of natural selection • Summarize the four principles of natural selection 10.3 Theory of Natural Selection KEY CONCEPT Darwin proposed natural selection as a mechanism for evolution. 10.3 Theory of Natural Selection Vocabulary • Artificial Selection – process by which humans modify a species by breeding it for certain traits (304) • Heritability – ability of a trait to be passed from one generation to the next (304). • Natural selection – mechanism by which individuals that have inherited beneficial adaptations produce more offspring on average than do other individuals (305). • Population – all of the individuals of a species that live in the same area (306). • Fitness – measure of an organism’s ability to survive and produce offspring relative to other members of a population (307). 10.3 Theory of Natural Selection Who Developed the Theory of Evolution by Natural Selection? • Charles Darwin • His observations: – Variation: The difference in the physical traits of an individual from those of other individuals in a group. – Adaptation: The features that allow an organism to better survive in its environment Example: The different beak types of different Galapagos finch species. − Fossils: found evidence of species changing over time which lead him to believe Earth was much more than 6000 years old. 10.3 Theory of Natural Selection Several key insights led to Darwin’s idea for natural selection. • Darwin noticed a lot of variation in domesticated plants and animals. • Artificial selection is the process by which humans select traits through breeding. neck feathers crop tail feathers 10.3 Theory of Natural Selection • Natural selection is a mechanism by which individuals that have inherited beneficial adaptations produce more offspring on average than do other individuals. • Heritability is the ability of a trait to be passed down. • Darwin proposed that adaptations arose over many generations. Artificial Selection • Imposed by humans • Selective breeding • Does not improve fitness • Genetic modification • Ex: dog breeds Natural Selection • • • • Diversity Variation Heritable Driven by natural processes/environment 10.3 Theory of Natural Selection •There is a struggle for survival due to overpopulation and limited resources. •A Population is all the individuals of a species that live in an area. •Example: All crows that are around Orange Glen High School. (ON THE NEXT PAGE) 10.3 Theory of Natural Selection Natural selection explains how evolution can occur. • There are four main principles to the theory of natural selection. – variation – overproduction – adaptation – descent with modification ADAPTATION VARIATION OVERPRODUCTION DESCENT with MODIFICATION 10.3 Theory of Natural Selection • Fitness is the measure of survival ability and ability to produce more offspring. • What if….. – A bird outcompletes other birds for food in a particular area and that bird can produce many more eggs, this bird has a high FITNESS 10.3 Theory of Natural Selection Natural selection acts on existing variation. • Natural selection can act only on traits that already exist. • Structures take on new functions in addition to their original function. five digits wrist bone 10.3 Theory of Natural Selection Exit Ticket • In your own words, what is the difference between Natural Selection and Artificial Selection. • What did Charles Darwin observe in the world that helped him to come up with his theory of Natural Selection? • List the 4 main principles of Natural Selection