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Adaptations and Natural selection. 7.11B explain variation within a population or species by comparing external features, behaviors, or physiology of organisms that enhance their survival such as migration, hibernation, or storage of food in a bulb. Key terms.
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Adaptations and Natural selection 7.11B explain variation within a population or species by comparing external features, behaviors, or physiology of organisms that enhance their survival such as migration, hibernation, or storage of food in a bulb
Key terms • Species: a group of organisms that have similar genetic characteristics that can interbreed in and produce fertile offspring Examples: Wild horse species: ferusDomestic dog species: familaris
Key terms • Population: a group of individuals of the same species in a specific area Example: A group of deer
Key terms • Species diversity: the variety and abundance of species in a given area (biodiversity) Example: in this one area there are many different species of plants.
Key terms • Genetic diversity: the variety of inheritable characteristics in a population of species. Example: these dogs are all the same species
Stop and discuss: What are some environmental challenges that all organisms face ?
Environmental challenges that limit survival: • number of predators • Living space • ability to reproduce • number of offspring • severe weather • access to food and water (famine or drought) • competition for food
Species Diversity • Variation of traits within a population helps the species survive over time • Peppered Moth Video and Worksheet
What kind of variation exists within a species? • Size / weight • Color • Patterns • Speed • Number of offspring • Physical features • Behaviors
Adaptation • A structure, behavior or physiological process that an organism has that helps an organism survive and reproduce in a particular environment
3 Categories of Adaptations • Structure: any physical feature that helps the organism survive • Behavior: something that an organism does... an action that helps them survive. • Physiology: a body function that helps organisms survive.
Structural Adaptations Examples: • Coloring/ camouflage • Mimicry • Fat • Beak shape • Bulbs for storage
Camouflage Stick insect Gecko Gecko Seahorse Snake Frog
Mimicry Mimicry: 1. a structural adaptation in which a harmless species resembles a harmful species in coloration or structure. 2. when two organisms, that are harmful mimic each other’s warning signal. This increases the chance even more of predator avoidance.
Behavioral • Behavior Adaptation: something that an organism does... an action that helps them survive. • mating times • migration • nocturnal activities These behaviors enable organisms to find available resources or favorable conditions for reproduction
Physiological • Physiological adaptation: a body function that helps organisms survive. • Hibernation • Tolerance to temperature / salt / chemicals • Production of venom
How do Adaptations Develop? 1. Natural selection
How do adaptations develop? • Selective breeding Controlled breeding to get Desired traits.