Quest 1 Flashcards
What is fitness?
Survival and reproduction rate
Differential Reproductive Success
Individuals with certain traits are more successful than others at surviving and reproducing in their environment
Descent with modification
Pattern of evolution
To understand the evolution of a species we must know the ancestral species it DESCENDED from and what MODIFICATIONS have occurred along the way
Phylogenetic diversity
A measure of biodiversity that incorporates the evolutionary relationships between species.
Mutation
Random change, the top driver of natural selection, without there is no genetic diversity
Life History Strategy
Schedule and manner of investment in survivorship and reproduction over the lifetime of an individual
The overall plan an organism uses to grow, reproduce, and survive over its lifetime. It reflects how the organism allocates its energy and resources to these key activities in order to maximize its chances of passing on its genes
Life History Traits
Traits ta govern life history strategy, lead to trade offs in a biological system
Age at first reproduction, number of offspring, lifespan, growth rate, reproductive frequency
Antibiotic resistance
Example of evolution ion pharmaceuticals, bacteria is no longer taken out by antibiotics
Speciation
The process by which one species splits into two or more new species. Happens when groups of the same species becomes isolated and evolve differently overtime until they can no longer reproduce with one another
Genotype
The genetic makeup of an organism and all the genes it carries
Phenotype
Observable characteristics or traits of an organism as a result from the interaction of the organism’s genotype with the environment
Extinction
Permanent disappearance of a species
Uniformitarianism
Current geological processes taking place now are the ones that sculpted the earth
Charles Lyell
Norm of Reaction
The range of phenotypes that a single genotype can produce in response to different environmental conditions
Illustrates how organisms with the same genetic makeup can exhibit different traits depending on their environment
Three steps of Natural Selection
- Variation - Individuals in a population differ
- Inheritance - Some of these differences are inherited by offspring from their parents
- Differential Reproductive Success - Individuals with certain traits are more successful than others at surviving and reproducing in their environment
Artificial Selection
Selective breeding, humans select and breed individuals with desirable traits to produce offspring
Adaptation
Inherited trait that makes an organism more fit in its abiotic and biotic environment, and that has arisen as a result of direct action of natural selection for its primary function.
Exaptation
Trait that serves a purpose now, but evolved another under different selection pressure
Inheritance of Acquired Characteristics
First theory of transformation and adaptation of species
Pleiotropic Genes
When genes affect more than one characteristic
Antagonistic Pleiotropy
Genes that code for beneficial effects in one case code for deleterious effects in other contexts
Complex traits
Characteristics influenced by multiple genes and environmental factors, rather than being determined by a single gene
What are the two hypotheses of the Evolution of Complex Traits?
- Each intermediate step along the way was adaptive and selected for and served a purpose similar to what the complex trait does now.
- Each intermediate step along the way was adaptive and selected for but served a different purpose and were co-opted to serve a new purpose in the complex trait.
6 Constraints to Evolution
- Genetic variation – without it NS is useless.
- Gene constraints – Genes may be constrained by other processes they contribute too.
- Gene flow – Outlining pops may not be able to locally adapt if gene flow is continuous
- Physical Constraints
- Arms races - Adaptations hinge on the abiotic and biotic environment
- Evolution lacks foresight
Gene sharing
Protein serving one function is recruited to serve another function elsewhere
Gene Duplication
A process in which a segment of DNA containing a gene is copied, resulting in two or more copies of that gene within the genome
Vestigial organs
Structures in an organism that have lost most or all of their original function through evolution
C. Darwin’s 2 fundamental insights
- The environment selects on variation of traits of individual organisms, successful variants reproduce
- Common ancestry of organisms
E.Darwin
Book: Zoonomia
Life from a single living filament
E.Darwin’s Failures
- He did not connect that the struggle for existence caused evolutionary change
- Acquired traits are passed on
Wallace
Independently developed a theory of evolution by natural selection very similar to that of Darwin
Lamarck
Inheritance of acquired characteristics (First theory of transformation and adaptation of species)
Species evolve independently
Lyell
Gave us UNIFORITARIANISM vs CATASTEROPHISM
Helped pave the way for modern evolutionary thinking
Aristotle
Used the methodological naturalism to formulate hypotheses
The scala naturae
The scala naturae
an unbroken chain of increasing complexity in animals
Lead to the Spontaneous Generation Theory
Aristotle’s scala naturae flaws
Shared degrees of complexity
Potential to change
Relative Dating assumptions
- Principle of superposition - young over old
- Principle of horizontality - Non horizontal happened secondarily
- Principle of cross cutting relationships - Rocks in seams are younger
- Principle of inclusions - Boulders found in body of rocks are old
- Principle of faunal succession - Early are more simple, recent are most like existing
Darwin insight 2
Descent with modification
Common Ancestry
Explained 2 levels to see truths of living species (cluster and hierarchy)
Darwin’s take on species
Varieties become subspecies which become species
Species = strongly marked with permeant changes
Darwin insight 1
Natural selection
Variation is key to the process
Variation + stress brings power to natural selection
Problems with Darwin’s theory
- Complex structures with intricate parts
- Vestigial organs
- Running out of variation
Evolution
A science to explain where the earth’s organisms came from, why there are so many and how they became so well designed
Methodological Naturalism
Only accept hypotheses and explanation grounded in strictly natural causes
Coevolution
When one species can affect selective conditions of other species
