Hobbies And Interests
Functions
Structural adaptations can affect the shape of an organism, its coloring or a particular body part. These changes allow an organism to procure nourishment, withstand extreme environmental conditions, guard against predators and reproduce successfully. To illustrate, the Boston ivy's modified leaves produce a sticky substance that allows the vine to adhere to surfaces so the plant can obtain more sunlight.
Theory of Evolution by Natural Selection
The theory of natural selection, or "survival of the fittest," proposed by naturalist Charles Darwin, suggests that certain factors in an environment will favor organisms with beneficial characteristics. These organisms will reproduce more successfully and pass on those same advantageous characteristics to subsequent generations. Over time, unfavorable characteristics will disappear, while favorable ones will remain within the population of a species.
Misconception
Before the advent of the theory of evolution by natural selection, French botanist and naturalist Jean Baptiste Lamarck proposed that anatomical structures appeared or modified because the organism used those body parts repeatedly; these traits then transferred to offspring. Lamarck illustrated his premise using the giraffe, hypothesizing that the giraffe acquired its long neck by stretching it to reach the leaves of tall trees. Offspring would inherit the long necks, but could make their necks longer by stretching them even further. Scientists later rejected Lamarck's mechanism of evolution.