Why do some vertebrate animals have forelimbs that have similar bones but different functions?
Because they share a common ancestry.
Primitive features in organisms, such as teeth and nails, the do appear in ancestral forms
Ancestral traits
This adaptation refers to an organismś ability to blend in to its surroundings, or to be hidden
Camouflage
The study of the distribution of plants and animals around the world
Biogeography
This can occur in a harmless species that chooses to look like a deadly species
Mimicry
Anatomical structures inherited from a common ancestor
Homologous structures
cumulative changes in groups of organisms through time.
Evolution
An early prebirth stage of an organism´s development
Embryo
An adaptation in which one organism tries to imitate another one
Mimicry
When a population declines to a very low number and then rebounds, the new population is genetically similar to that of the population when it was at its lowest level
Bottleneck.
These have either a reduced function or no function at all in an adult organism
Vestigial Structures.
Three parts of evolution
Variation, Overproduction, Competition, Selection, Descent with modification
Features in different organisms that can be used for the same purpose and can be superficially similar in construction but are not inherited from a common ancestor
Analogous Structures
In evolutionary theory, individual organisms do not evolve- What actually evolves is this
The population of animals
This form of natural selection eliminates extreme expressions of a trait
Stabilizing selection
Some examples of vestigial structures
Tailbone in humans, emu wings, Wisdom Teeth, Appendix
The process of directed breeding to produce offspring with desired traits.
Artificial selection
In fish these become gills, in mammals theybecome parts of the ears, jaws and throat
Pharyngeal pouches
The measure of the relative contribution that an individual trait makes to the next generation
Fitness
If an extreme version of a trait makes it more fit , this can occur
directional selection
Newly evolved features that do not appear in the fossils of common ancestors
Derived Traits
This was the name of Charles Darwin´s book
The Origin of Species
One way used to study evolutionary relationships involving the analysis of complex metabolic molecules
Comparitive molecular biology
At least two advantages of camouflage
Being able to hide from predators
Being able to hide from prey
A type of natural selection in which the change in frequency of a trait is based on the ability to attract a mate
Sexual selection