Exam 1

Chapters 22-24

Evolution

process by which species accumulate differences from their ancestors as they adapt to different environments over time

* summarized by Darwin’s phrase descent with modification

Carolus Linnaeus

developed a nested classification system grouping similar species into increasingly inclusive categories

* developed the binomial format for naming species

Fossils

remains of organisms from the past

Strata

fossils are found in sedimentary rock, which appears in layers called …

Paleontology

the study of fossils

Georges Cuvier

observed that older strata contain fossils less similar to current organisms than more recent strata

* discovered that, from layer to layer, new species appear while others disappear
* Paleontology was developed in large part by ___
* speculated that boundaries between strata represent sudden catastrophic events

Catastrophism

that natural history has been punctuated by ________ event that altered that way life developed and rocks were deposited

James Hutton

proposed that Earth’s geologic feature were formed gradually

ex. valleys being formed by rivers

Charles Lyell

proposed that the same geologic processes operate today as in the past, at the same rate

* what ever changed the environment, it is still going, still going and being carved out

Jean-Baptiste de Lamarck

propose 2 principles to explain evolutionary change

* use and disuse: body parts used extensively become larger and stronger, unused part deteriorate
* inheritance of acquired characteristics: modifications acquired in one’s lifetime can be passed to offspring

Adaptations

are inherited characteristics that enhance an organism’s survival and reproduction in specific environments

Natural selection

a process in which individuals with certain inherited traits tend to survive and reproduce at higher rates because of those traits

Descent with modification by natural selection

____ explains

* The unity of life
* The diversity of life
* The ways organisms are suited to life in their environments

Descent with Modification

related organisms living in different habitats gradually accumulated diverse modifications to fit them to specific ways of life

* all organisms are related by descent from a common ancestor that lived in the past

Artificial selection

humans modify species, breeding only individuals with desired traits