Changes And how they affect evolution Behavioral Changes

Changes And how they affect evolution

Behavioral Changes • Behavioral Isolation: Isolation caused by differences in courtship or mating behaviors. • Sexual Selection: The choosing of a mate due to specific physical traits. • Female birds choosing mates due to dances, songs, or feather patterns • Birds of Paradise video • Patterns of flashes for fireflies • Cow elk breeding with the bull who wins the fight

Behavioral Changes • Temporal Isolation: When timing prevents reproduction between populations. Some members of a population may show signs of courtship at different times if there is a lot of competition for mates. Reproductive periods may change to a different time of the year or a different part of the day. These differences in timing can lead to speciation. • Trout

Behavioral Changes • Some behavior changes can lead to increased competition for limited resources. • Bowerbird video • https: //www. youtube. com/wat ch? v=GPb. WJPs. BPd. A&index=14 &list=PLsmmd. NCY 9 ges 2_h 9 ny_ W 7 I-a. M_db. U 1 s. PF

Morphological and Physiological Changes • Morphology: The form and structure of animals and plants. • Physical changes that result from organism’s behavior over long periods of time. • Sexual Selection: The choosing of a mate due to specific physical traits. • Males changing over time to mate more successfully with females. (Birds of paradise changing over time)

Morphological and Physiological Changes • Reproductive isolation: When two populations cannot reproduce and create viable offspring. It can be behavior, geographic, or genetic. Reproductive isolation occurs when formerly interbreeding organisms can no longer mate and produce fertile offspring.

Competition • Competition: When species must compete for a limited resource. If there is less food/resources, competition increases. • Brook trout vs cutthroat trout • Darwin’s finches competing for food • Competition between viable mates can lead to morphological changes • Peacock’s feathers being used to attract the peahen

Activity • Besides the examples given above, Give another possible example of each of the following: Behavioral change, Morphological/physiological change, Competition. • Questions • 1. Body parts of organisms that do not have a common evolutionary origin but are similar in function. • 2. Structures in different species that have a common evolutionary origin? • 3. How animals are formed from an egg to a developed organism.

Name that Change…. • 1. A population of brown trout spawn in the fall rather than other populations which spawn in the spring. • 2. A sage grouse will display a tail fan and beat two sacs in its chest to encourage a female to mate. The passing down of these display traits to the offspring can continue onto the next generation. • 3. Bowerbird build a nesting site which they decorate with various forest items to impress the females to mate. With a limited number of females, males are constantly changing their nests to be more impressive than the other males. • 4. A male peacock has an elaborate fan of feathers to impress the female peahens and encourage them to mate. The offspring will also have the traits of this elaborate fan of feathers.