Ch 22 Flashcards
Define Inheritance of acquired characteristics
Suggested by lammarck
-that Individuals develop their phenotype changes in response to environmental changes
-This phenotypic changes I’ve been passed on to their offspring
-
Define phenotype
The detectable trait of an individual.
In inheritance of acquired characteristics phenotypic changes are passed on to offspring
What is Darwin’s theory of evolution?
Evolution occurs by natural selection
based Variation among individuals in a population
does not follow a linear progressive pattern and it states that individuals with certain traits produce more offspring than others without these
What was some evidence of change through time and descended from common ancestors
- Data on earths age
- Extinction in the fossil record
- Transitional features in the fossil record
- The presence of vestigial trait
- The change in populations that can be observed today
- The geographic proximity of closely related species
- The existence of genetic, developmental, And structural  homologies
- The formation of new species from pre-existing species that can be observed today
What is the fossil record
Consists of all the fossils that have been found on earth and described in the scientific literature
Define extinct
Species that no longer exist
Define vestigial traits
A vestigial trait in an organisms is a reduced or incompletely developed structure that has no or slight function
Is evidence that species change over time
Ex:
Define phylogenetic tree
A diagram that illustrates the ancestor - descendant relationships among taxa
homologies
Evidence of change over time
Define homology
Is a similarity that exists in species descended from a common ancestor
It can be recognized by :
- Genetic
- Developmental
- Structural 
Define developmental homology
Is similarity of an embryonic form or developmental processes that is due to inheritance from a common ancestor
Structural homology
Similarities in adult organism more structures that are due to inheritance from a common ancestor
Example: limbs 
What does genetic homologles cause?
Cause developmental homologies observed in embryos then developmental homologies lead to structural homologies
Speciation
Is a process that results in one species splitting into 2 or more descendant species
Internal consistencies
The observation that data from independent sources agree in supporting predictions made by a theory and is the most powerful evidence for any scientific theory
Artificial selection
Deliberate manipulation by humans as an animal and plant breeding of the genetic composition of a population by allowing only individuals with desirable traits to reproduce
What are the 4 criteria (postulates) of Darwin’s evolutionary process by natural selection?
- Individuals in a population vary in their traits
- Some of these differences are heritable; they are passed onto offspring
- In each generation many more offspring than others
only some survive long enough to reproduce
some will produce more offspring than others - ## Individuals with certain heritable traits Are more likely to survive and reproduce
Adaptation
Heritable trait that increases an individuals fitness in a particular environment relative to individuals lacking that trait the more favored trait will be increased in frequency in pop.
Occur when the allele frequencies in a population change in response to natural selection but they do not occur because organisms want or need them
Polygenetic trait
Any trait that is influenced by more than one gene polygenic traits are usually quantitative traits
Example: beakdepth
Acclimatization
Occurs when an individuals phenotype changes in response to changes in the environment and the individuals genotype remains fixed or the Changes to offspring are not passed down because no alleles have changed