Station 1: Patterns
Station 2: Mechanisms of Evolution
Station 3: Microevolution, Speciation, Macroevolution, Big Issues
Microevolution- Evolution on a small scale
Macroevolution- Evolution on a grand scale
Big Issues:
Adaptive Radiation
Historical changes
Co-opting
- 3 domains of life- eukaryota, bacteria, archaea
- Phylogeny- evolutionary relationships between species
- Clades- Domains of life
- How are phylogenies usually read?- The root of the tree is like the ancestor and each branch is a descendant of that ancestor. Root to tips= going forward in time
- What do we mean by tree-like, not ladder like?- There is a branching pattern. There is no level of advancement.
- Character- Attribute of an organism (Physical and actions)
- Shared character- It’s a character that 2 lineages have in common
- Derived character- It’s the evolution of an organism that leads to new characteristics setting members of one clade different for another
- Homologies- Characters in different organisms that come from the same ancestry making them very similar
- Analogies- Organisms that grow into similar characters but don’t come from the same ancestry
- Convergent evolution- the process that occurs when two distinct lineages evolve a similar characteristic independently of one another.
- Linnean system of classification-The standard system of classification in which every organism is assigned a kingdom, phylum, class, order, family, genus, and species. This system groups organisms into ever smaller and smaller groups
- Phylogenic system of classification- It names groups of organisms according to their evolutionary history
- Which system is being used more and more and why?
- Cite 3 types of evidence of evolution: Radiometric dating, Stratigraphy, Molecular clocks
Station 2: Mechanisms of Evolution
- Evolutions only occurs when?- It occurs when there is a change in gene frequency in a population
- Describe 4 mechanisms of evolutionary change
- Mutation- Possible errors in one’s DNA sequence can alter the gene pool
- Migration- Inbreeding of different genes from different regions can cause alteration in the evolutionary process
- Genetic Drift- Changes by chance that can alter the gene pool that may prevent a one’s ability to breed
- Natural Selection- Certain genes can allow for predators or can inhibit death on an organism and these genes may eventually die off and alter the gene pool and frequency
- Describe 3 sources of genetic variation
- Mutations- Changes in DNA can cause a genetic variation
- Gene Flow- Gene movement from on population to another affects the gene pool
- Sex- It can introduce new gene combinations and allows for variation
- Name 2 causes of mutations
- DNA can copy information incorrectly and lead to mutations
- Exposure to chemicals and radiation can cause mutations at the genetic level
- Gene Flow- any movement of genes from one population to another and is an important source of genetic variation
- Development- process in which an embryo becomes an adult and eventually dies
- Genetic Drift
- What is it? -the constant change in which a population that has a specific trait can decrease over generations
- What does it not produce?-Adaptations
- Fitness- How good a genotype is at passing down its trait to the next generation
- Sexual selection- natural selection acting on mate-finding and reproductive behavior/an organisms ability to successfully obtain a mate
- Artificial selection- people rather than nature select the organisms which reproduce
- Adaptation- feature that is common amongst a species and is produced by natural selection
- Cite 2 misconceptions concerning natural selection
- natural selection is not all-powerful and does create the perfect organism
- natural selection is more of a process than a guiding hand
- Coevolution- Evolution in which 2 or more species evolve reciprocally/It is usually involved with predator/prey, parasite/host, competitive species, and mutualistic species relationships
Station 3: Microevolution, Speciation, Macroevolution, Big Issues
Microevolution- Evolution on a small scale
- Species- a group of individual interbred in nature
- Gene pool- all of the genes in a population/ any genes that could wind up in the same individual
- Speciation- an event that splits a lineage producing 2 or more separate species
- Describe 2 causes of speciation
- Allopatric speciation- When isolation causes the altering and the separation of a single species and they begin to form 2 different ones
- Incipient species- A group of organisms that could become it’s own species to to their isolation from the rest of the species
- Co-speciation- When the correlation between 2 species is close they may be able to speciate in parallel
Macroevolution- Evolution on a grand scale
- Generally refers to evolution above the species-level
- Stasis- Lineage does not change much over a period of time
- Character Change- Change that can take place
- Speciation- lineage splitting
- Extinction- An entire species no longer existing
Big Issues:
- Does evolution proceed slowly and steadily or in quick jumps?
- Why are some clades very diverse and some unusually sparse?
Adaptive Radiation
Historical changes
- How does evolution produce new and complex features?
Co-opting
- Are there trends in evolution? if so, what processes generate them?