ADAPTATIONS OVER TIME 1. A species is a group of organisms that can mate and produce fertile offspring. 2. A fossil is the preserved remains or traces of an organism that lived in the past. 3. A variation is an inherited trait that makes an individual different from other members of its species. 4. An adaptation is a variation that makes an organism better suited to its environment so that it can survive, reproduce, and pass its traits on to its offspring. 5. Charles Darwin developed the theory of evolution based on natural selection

Charles Darwin

6. The word evolution means change over time. 7. Natural selection is the process by which individuals of a particular species are better adapted (they have certain traits that make them better suited to survive) to their environment and are more likely to survive and reproduce (passing their traits to future generations) than other members of the same species

Most species produce far more offspring than can possibly survive 8. Darwin identified 3 factors that affect the process of natural selection: a. Overproduction Most species produce far more offspring than can possibly survive b. Competition Organisms compete for food, space, water, light, mates, etc. c. Variations Individuals inherit genetic differences. Variations can result from genetic mutations (many times are harmful) and the shuffling of alleles During meiosis (the process that forms the sex cells).

9. For example, Darwin traveled to the Galapagos Islands and observed that different finches have different shaped beaks according to the food that it eats. Finches with long, pointy beaks could pick insects from tree bark. Finches with harder, more rounded beaks could grind large seeds and fruits.

10. Another example is the story of the peppered moth. a. When newly industrialized parts of Britain became polluted in the nineteenth century, smoke killed lichens growing on trees and blackened their bark. b. Pale colored moths which had been well camouflaged before when they rested on tree trunks became very conspicuous and were eaten by birds. c. Rare dark moths, which had been conspicuous before, were now well camouflaged in the black background. d. As birds switched from eating mainly dark moths to mainly pale moths, the most common moth color changed from pale to dark.

12. All organisms have adaptation that help them to survive 11. Environmental changes, mutations, shuffling of alleles, geographic isolation, and man (selective breeding) can affect natural selection or which organisms can best survive in a particular environment. 12. All organisms have adaptation that help them to survive a. mimicry – acting or looking like another organism that is dangerous. b. camouflage – physical appearance that allows an organism to hide from predators or prey. c. venom – poisonous matter secreted by some organisms.

d. Warning coloring – red, yellow **WARNING** e. Speed f. Alertness c. Protective covering – shell, scales d. Warning coloring – red, yellow **WARNING** e. Speed f. Alertness g. Odors h. Groups

QUESTIONS: ADAPTATIONS OVER TIME NAME: _______________________________________ 1. Define variation. __ _______________________________________________________ _______________________________________________________________________ 2. What is natural selection? __________________________________________________ ________________________________________________________________________ 3. How do variation and natural selection work together to help an organism better adapt to its environment? ______________________________________________________________ 4. Describe the relationship between variation and adaptation. _______________________ 5. Suppose the climate in an area becomes much drier than it was before. What kinds of variations in the area’s plants might be acted on to help the plants adapt and survive? QUESTIONS: ADAPTATIONS OVER TIME NAME: _______________________________________ 1. Define variation. _________________________________________________________ _______________________________________________________________________ 2. What is natural selection? __________________________________________________ ________________________________________________________________________ 3. How do variation and natural selection work together to help an organism better adapt to its environment? ______________________________________________________________ 4. Describe the relationship between variation and adaptation. _______________________ 5. Suppose the climate in an area becomes much drier than it was before. What kinds of variations in the area’s plants might be acted on to help the plants adapt and survive?

8. How do variations occur? 6. What roles do the overproduction of organisms and competition play in natural selection?______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________ 7. How can natural selection lead to changes in a species? __________________________________________________________________________________________________________________________________________________________________ 8. How do variations occur? _________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

11. List 5 adaptations organisms may have to aid in survival. 9. List the three factors that can affect natural selection. ____________________________________________________________________________________________________________________________________________________________________________________________________________________ 10. Give an example of natural selection. ________________________________________________________________________________________________________________________________________________________________________________________________________________________ 11. List 5 adaptations organisms may have to aid in survival. __________________________________________________________________________________________________________________________________________________________________

12. Define mimicry. ______________________________________________________________________________________________________________________________ 13. Define venom. ______________________________________________________________________________________________________________________________ 14. Define camouflage. ______________________________________________________________________________________________________________________________

Answers to questions - Adaptations over time. 1. A variation is an inherited trait that makes an individual different from other members of its species. 2. Natural selection is the process by which individuals of a particular species are better adapted to their environment and are more likely to survive and reproduce.

3. Individual organisms have variations. These different characteristics can lead to natural selection when they help an organism survive and reproduce. 4. A variation that allows an organism to better survive is an adaptation. 5. Plants that have thicker waxier leaves to prevent water loss and plants that can store water would better survive.

6. Overproduction of offspring can lead to competition among the offspring for food, water, space, and so forth. 7. Natural selection is a process by which the best adapted individuals survive and reproduce therefore passing their traits on to their offspring. As generations continue to pass these traits to their offspring, changes in the species can occur.

9. Overproduction Competition Variations 8. Variations are inherited genetic differences that can result from mutations or the interactions of the alleles. 9. Overproduction Competition Variations 10. Birds beaks are adapted to eat certain foods. The peppered moths that were best camouflaged survived.

13. Venom is a poisonous substance. 11. mimicry, camouflage, venom, protective covering, coloring, speed, alertness, odors, staying in groups, nasty taste 12. Mimicry is acting or looking like another organism that is dangerous 13. Venom is a poisonous substance. 14. Camouflage is a physical appearance that allows an organism to hide form predators or prey.