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Ch 6 Natural Select

A group of organisms that share similar characteristics are called a __________ Species
Animals that can reproduce among themselves and produce fertile offspring are members of the same __________ Species
What do we call changes in inherited characteristics over time? Evolution
Who believed that characteristics parents had developed over their lifetimes(like large muscles from exercise)could be passed to their offspring? Lamarck
He studied finches on Galapagos Island, and found they were all similar to one type of finch. Darwin
Who believed that finches changed as they competed for food? Darwin
What idea states that organisms with traits best suited for the environment survive and reproduce, passing traits to their offspring, while unfavorable traits die off with offspring who do not survive? Natural Selection
What do we call an inherited trait that makes an individual different from other members of its species? A variation
Mutations can cause these: Variations
Beneficial mutations that are more likely to be passed on due to natural selection Variations
Changes in a species that can take a long time to appear are called Variations
Changes that appear when members of the same species move into or out of an area are a form of Variation
Isolating a small number of individuals may cause variations to occur that are not present in other populations of the same species in a process called Variation
Populations can become so different over time because of isolation that they cannot breed (reproduce). Variation
A variation that increases an organism's chance for survival is called this An adaptation
What do we call the slow process where one species changes into another? Gradualism
What do we call the rapid evolution the occurs when individuals mutate and pass on those mutations/traits? punctuated equilibrium
When bacteria become resistant to antibiotics, this is happening. punctuated equilibrium
What do we call the remains or traces of once living organisms Fossils
Where are fossils usually found? Sedimentary rock
Carbon that is left when an organism decays and may harden into rock is called An imprint
When sediments fill in the cavity left by a decaying organism, they make a _________ cast
The impression or cavity left by the shape or a track of an organism mold
An estimate about the age of a fossil based on the location in the rock is ___________ dating. relative dating
In relative dating, the older fossils are found _____________________ in the rock farther down
This type of dating is based on the amound of time it takes for 1/2 of radioactive material to decay. Radiometric dating
Radiometric dating depends on the fact that radioactive material is unstable and decays at a set rate
This type of dating is more accurate for determining fossil age Radiometric dating
Carbon-14 has a half-life of how many years? 5700 years
Calculate age of the fossil (C-14:5700 year) This fossil has decayed through 2 half-lives 11,400 years
Calculate age of the fossil (C-14:5700 year) This fossil originally had 100 gms of C-14 and now has 25 grams 11,400 years
Seen early in embryonic development, these are similar in human and other vertebrate embryos, and used to link species Embryonic structures
Parts that function in one organism, but not another (like the tailbone)and may show a common ancestor Vestigial Structures
These structures that are developmentally similar but have different functions (arm/flipper)may also show common ancestry. Homologous Structures
Similarities in this shows common ancestry DNA
Name 3 characteristics of primates * opposable thumbs * binocular vision * flexible shoulders
How are these organisms alike: monkeys, apes, and humans? They are in the same primate group
What first appeared 4-6 million years ago? hominids
What are two characteristics of hominids? They walk upright; they eat both plants and meat.
An example of this organism which has a small humanlike brain, and similar teeth and lived 2.9-3.4 million years ago was named "Lucy" when it was discovered. Australopithecus
Coming after Australopithecus, evidence shows they used simple tools homo habilis
Coming after homo habilis, these had a larger brain homo erectus
Appearing 400,000 years ago, these followed homo erectus homo sapiens
These hominids appeared 125,000 years ago Cro-magnon/Neandethals
What are four things we know about Neanderthals? * They lived in caves * They used stone tools * They were short with small chins * They disappeared about 30,000 years ago
What do we know about Cro-magnons? * They appeared about 10,000-40,000 years ago * They were more similar and closely related to modern Humans * They lived in caves, and painted on their walls * They had a developed culture, and buried their dead.
Created by: judi829