what is speciation
Speciation is the process by which new species develop from changes to preexisting species from natural selection and mutation that create whole new species that can no longer interbreed.
What causes speciation?
divergence between the genetic population being able to have gene flow between the two pools. Most is thought to be allopatric meaning physical separation of species either by geography or a small group being outside the main groups normal range.
What is the biological species concept?
Actual or potential breeding species that are reproductively isolated from other such groups
What are the limitations of biological species concept and what are the advantages of alternative species concept?
The biological species concept cannot account for fossil evidence and hybridization. The alternative species concepts may look at species through niche and DNA rather than just if the species is capable of mating.
What is a phylogenetic tree?
A phylogentic tree is a graph that helps us visualize how all life is connnected.
What are homologous characteristics?
Characterisitcs shared ancestrally
What are analogous characteristics?
Recently gained characteristics based on mutation
Compare homologous and analougous characteristics
you will see homologous characteristics going back for several species in the phylogenetic tree, analogous characteristics are typically unique to one species in the group.
What is cladistics?
A biological organization system that organizes groups of organisms based on shared characteristics to map relationships
How is classification informed by cladistics?
Explain the importance of transitional fossils as evidence for all common decent.
transitional fossils prove that species formed into other species and that changes among the species happened gradually. it showed the change from ape into modern man or from land mammal into whales.
What can prevent hybridization?
Difference in mating practices, calls not being recognized between species, differences in genetics.
what are tinbergs four questions?
How did the behavior develop?
What mechanism does this behavior serve?
How did this behavior evolve?
What adaptations in the environment cause this behavior?
How do we know a behavior is learned?
If an animal is not displaying a behavior that is shown by the rest of the group because they grew up in isolation, we know that behavior is learned.
How do we know a behavior is genetic?
The behavior will show up even in isolated individuals or from birth.
How do animals navigate?
Map navigation- where you are based on your landscsape
Magnetic- using the earths magnetic pull
Sun compass- Sun as a way to keep time and location
Kineisis- Random movements
Taxis- in response to simtulus
Why is communication important?
Reproductive needs, sharing information such as danger, and communication between kin and parents, also to convey information such as honey bees such as where supplies are
How is communication shared?
Some is taught by other members of the species in the imprinting phase based on what the baby bird hears.
What is cooperation in social groups
working together towards a common goal
Why does cooperation occur
An individual gets something out of it
what is group altruism
Sacrifice for the good of the group, they help each other out.
what is group selection
an idea that natural selection works on a group of organisms is a more powerful force than what works on individuals.
