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Some kinds of plants and animals that once lived on Earth are no longer found anywhere. (3.LS4.1)
Fossils provide evidence about the types of organisms that lived long ago and also about the nature of their environments. (3.LS4.1)
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Comparison of embryological development of different species also reveals similarities that show relationships not evidence in the fully-formed anatomy. (8.LS4.3)
The collection of fossils and their placement in chronological order (e.g., through the location of the sedimentary layers in which they are found) is known as the fossil record. It documents the existence, diversity, extinction, and change of many life forms throughout the history of life on Earth. (8.LS4.1, 8.LS4.2)
Anatomical similarities and differences between various organisms living today and between them and organisms in the fossil record serve as evidence of ancestral relationships among organisms and changes in populations over time. (8.LS4.2)
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Genetic information provides evidence of common ancestry and diversity. DNA sequences vary among species but there are many overlaps; in fact, the ongoing branching that produces multiple lines of descents can be inferred by comparing the DNA sequences of different organisms. Such information is also derivable from the similarities and differences in amino acid sequences and from anatomical and embryological evidence. (B.LS4.1) |
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Sometimes the differences in characteristics between individuals of the same species provide advantages in surviving, finding mates, and reproducing. (3.LS4.2) |
Natural selection leads to the predominance of certain traits in a population and the suppression of others. (8.LS4.4)
In artificial selections, humans have the capacity to influence certain characteristics of organisms by selective breeding. One can choose desired parental traits by genes, which are then passed on to offspring. (8.LS4.5)
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Natural selection occurs only if there is both (1) variation in the genetic information between organisms in a population and (2) variation in the expression of that genetic information - that is, trait variation that leads to differences in performance among individuals. (B.LS4.2, B.LS4.3)
The traits that positively affect survival are more likely to be reproduced, and thus are more common in the population. (B.LS4.3)
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For any particular environment, some kinds of organisms survive well, some survive less well, and some cannot survive at all. (3.LS4.3)
Changes in an organism's habitat are sometimes beneficial to it and sometimes harmful. (3.LS4.3)
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Adaptation by natural selection acting over generations is one important process by which species change over time in response to changes in environmental conditions. (8.LS4.6)
Traits that support successful survival and reproduction in the new environment become more common; those that do not, become less common. Thus, the distribution of traits in a population changes. (8.LS4.6)
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Natural selection leads to adaptation, that is, to a population dominated by organisms that are anatomically, behaviorally, and physiologically well suited to survive and reproduce in a specific environment. That is, the differential survival and reproduction of organisms in a population that have an advantageous heritable trait leads to an increase in the population of individuals in future generations that have the trait and to a decrease in the proportion of individuals that do not. (B.LS4.3, B.LS4.4)
Adaptations also means that the distribution of traits in a population can change when conditions change. (B.LS4.3)
Changes in the physical environment, whether naturally occurring or human induced, have thus contributed to the expansion of some species, the emergence of new distinct species as populations diverge under different conditions, and the decline and sometimes extinction of some species. (B.LS4.4, B.LS4.5)
Species become extinct because they can no longer survive and reproduce in their altered environment. If members cannot adjust to change that is too fast or drastic, the opportunity for the species' adaptation over time is lost. (B.LS4.5)
Evolution is a consequence of the interaction of four factors: (1) the potential for a species to increase in number, (2) the genetic variation of individuals in a species due to mutation and sexual reproduction, (3) competition for an environment's limited supply of the resources that individuals need in order to survive and reproduce, and (4) the ensuing proliferation of those organisms that are better able to survive and reproduce in that environment. (B.LS4.1)
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| There are many different kinds of living things in any area and they exist in different places on land and in water. (2.LS4.1) |
Populations live in a variety of habitats and change in those habitats affects the organisms living there. (3.LS4.4) |
Changes in biodiversity can influence humans' resources, such as food, energy, and medicines, as well as ecosystem services that humans rely on - for example, water purification and recycling. (7.LS2.5) |
Biodiversity is increased by the formation of new species (speciation) and decreased by the loss of species (extinction). (EN.LS2.7)
Human depend on the living world for the resources and other benefits provided by biodiversity, but human activity is also having adverse impacts on biodiversity. Thus, sustaining biodiversity so that ecosystem functioning and productivity are maintained is essential to supporting and enhancing life on Earth. (EN.LS2.7)
Sustaining biodiversity also aid humanity by preserving landscapes of recreational or inspirational value. (EN.LS2.7)
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