Evolution 16.3 and 16.4
_____________ refers t any structural, function, or behavioral characteristics of an organism that helps it better survive in its environment
Adaptation
They differ in the form and function, but are constructed from __________________
Basic bones
Natural selection- explains how overtime , species become __________ to their environment as they reside to selection pressures
Better suited
____________ is the study of where organisms live now and where they are their ancestors lived in the past.
Biogeography
Another example similar ones and forelimbs f a wi b of a bat, wing of a bird, flipper of a whale, foreleg of a horse, and the arm of a human. There are similar bone structures, so the forelimbs of all these species are thought to have developed from a _______________
Common ancestor forelimb(common ancestory)
He also proposed that living species are descended, with modification, from __________________—an idea called ___________________________________________.
Common ancestors, descent with modifications
__________ night growth rates and a shortage of life's basic needs (water, food, space) would eventually force organisms to compete for resources
Competition
Example of natural selection is
Different types of finch beaks
_________ describes how well an organisms can survive and reproduce in its environment. Fitness results from ________
Fitness, adaptation
Darwin proposed that animals with similar structures evolved from a common ancestor with basic version of that structure
For example, the front limbs of amphibians, reptiles, birds, and mammals contain the same basic bones
For evidence of descent with modifications over long period of time, Darwin pointed to the _________
Fossil record
fossil record
Fossils formed in different layers of rock with evidence of gradual change overtime
Which statement is an agreement with Darwin's theory of evolution?
More offspring are produced than can possibly survive.
Two processes that result in variations that commonplace influence the evolution sexually reproducing species are ___________ and ____________
Mutations and genetic recombination
Variation so within a species are most likely the result f
Mutations and reproduction
The diversity within the wild bird species in the accommodation diagram can best be explain ed by which process
Natural selection
Individual s with characteristics that are__________to their environment either die without reproducing or leave few offspring and are said to have low fitness
Not well-suited
In an environment that undergoes frequent change, species that reproduce sexually may have an advantage over species that reproduce asexually because the sexually reproducing specimens produce
Offspring with more variety
Geographic Distribution of Living Things
On different islands of the Galapagos islands, finches were different, but still has similarities to those on the mainlaind.
Which statement is most closely relates t the modern theory of evolution?
Organisms best adapted to a changed environment are more likely to reproduce and pass their genes to,offspring
_____________ a species has the potential to produce more offspring than can possibly survive. Example: a maple tree releases hundreds of seeds in a single season
Overproduction
According to Darwin's theory of natural selection, the individuals who survive are most likely the ones best adapted to exist in their environment. Their survival s due to the
Possession of variables that maximize fitness
___________. Since the surviving "________" organisms will be the only members of a species left to reproach, their favorable traits will be passed on to the next generations
Reproduction, "fit"
fossils are usually found in _______________ rock-the oldest layer of rock is at the _________
Sedimentary rock, bottom
According to the three of natural selection p, why are some individuals more likely than others to survive and reproduction?
Some individuals are better adapted to exercise in their environments than others are.
A __________ occurs when the members of each species compete for food, water, living space, and other needs.
Struggle for existence
The diagram below shows the effect of spraying a pesticide on a population of insects over three generations. Which conceptually is represented in the diagram?
Survival of the fittest
This difference in rates of survival and reproduction is called _____________. In evolutionary terms, survival means reproducing and passing adaptations on to the next generation
Survival of the fittest
A weakness in Darwin's original theory of evolution was the
The genetic basis for variants was not explained
The teeth of carnivores are pointed and are good for puncturing and ripping flesh. The teeth of herbivores are flat and are good for grinding and chewing. Which statement best explains these observations?
The two types were f teeth most likely evolved as a result of natural selection
Which statement about the individuals within a population that survive to reproductive age is consistent with Darwin's theory of natural selection?
They are the ones best adapted to exist in their environments
Darwins theory of evolutionary is based on
Variation and natural selection
Variation
Variation within a species is important ti the survival of that species, especially when conditions are not favorable. Species A has the best chance of surviving because it has the most genes diversity. Genetic diversity provides for the chance that a trait might help an organism adapt and survive a change in its environment.
___________ Darwin was very familiar with the wide range of individual variable amount members of a species. He observed and noted this variation, although he could not explain its genetic basis. ** The main weakness of Darwin's was his _______ to explain the _________he observed
Variation, inability, and sources of variation
______________ are inherited from ancestors, but have lost much or all of their original function due to differences selection pressures acting on the descendants
Vestigial Structures
Indicates with adaptations that are _________ to their environment can survive and reproduce most successfully and are said to have high-fitness
Well-suited
The special characteristics that make an organism particularly well suited to its environment are known as
adaptations
A large factor in the struggle for existence is how well ___________ the organism is in the environment.
adapted
Similar patterns of embryological development provide further evidence that organisms have descended from a
common ancestor
All birds __________
descended with modification
Structures that are shared by related species and that have been inherited from a common ancestor are called
homologous body structures
The modern theory of evolution states that a basis for variation within a species is provided by
mutations
He proposed a theory based on the presence of variations among members of a species and their interaction with a process he called _________________________
natural selection
____________ depends on the ability of organisms to reproduce and leave descendants. Every organism alive today is descended from parents who survived and reproduced
natural selection
____________ is the process by which organisms with variations most suited to their local environment survive and leave more offspring
natural selection
___________ defines difference among individuals as a species
natural variation
Evidence that best supports the theory of biological evolution was obtained from the
study of fossil records
According to Darwin's theory of natural selection, the individuals that tend to survive are those that have
variations best suited to the environment
The natural environments "________" the varieties that will survive and those that will perish
"Selects.