Review

1. Review • Darwin’s theory of evolution: • Natural selection • Survival of the fittest • Adaptation to environment • Variation in species • Natural selection: over time advantageous traits will be found in more of the population • Biological theory of evolution: characteristics of simpler life-forms can be found in more complex life-forms • Trilobite fossils from different periods show small changes in appearance in response to environmental change

2. Review • Organisms which are more favored in an environment are more likely to survive • Adaptations in desert: • Small animals burrow into the ground during the day to avoid the sun’s heat and emerge only at night when temperatures are lower • Some plants have long taproots, enabling them to penetrate the water table deep within the ground • Many mammals have long tubes in their kidneys and produce highly-concentrated urine to conserve water • Adaptations in aquatic environment • Plants have broad leaves that float near the surface to access sunlight

3. Review • Adaptations that allow birds to fly: • Feathers, wings, hollow bones • Adaptations of crocodiles: • New sets of teeth grow in to replace lost teeth • Adaptations to survive in the taiga: • Needles do not need to be replaced every spring, increasing the amount of energy available for the short growing season • Adaptations of deep ocean organisms: • Able to withstand the high pressure of the water at extreme depths, so when brought to the surface, their bodies cannot cope with the relatively low pressure

4. Review • Adaptation of camels in the desert: • 2 rows of long eye lashes • Adaptation of giraffes: • Longer necks • Adaptation of mating in birds: • Females generally choose to mate with the “showiest” males • Adaptation of plants in areas with little sunlight: • Large leaves

5. Review Sponges are unable to move and can reproduce sexually or asexually Bacteria can display the most significant adaptations to their environment in the shortest period of time What will likely happen to a species that lacks the variation necessary to adapt to a changing environment? Adaptation is a term that describes a specially developed characteristic that enables an organism to live in a specific environment

6. Review • Asexual reproduction is one way organisms can increase their rate of survival • Example of asexual reproduction in plants: • A plant produces tiny plants around the edges of its leaves that fall to the ground, take root and become new plants • Most common negative result of asexual reproduction in organisms who normally reproduce sexually is ______