Exam one learning objectives Flashcards
What is the difference between natural selection and artificial selection?
Natural selection occurs through environmental pressures leading to survival and reproduction, while artificial selection is human-directed breeding for specific traits.
Artificial selection is often used in agriculture and animal breeding.
Who were some major thinkers that influenced Darwin?
Major thinkers include:
* Lamarck
* Lyell
* Malthus
* Wallace
Each thinker contributed ideas related to evolution, geology, and population dynamics.
What is the difference between Mendelians and biometricians in terms of inheritance?
Mendelians focused on discrete traits and inheritance patterns, while biometricians emphasized continuous variation and statistical analysis.
Their ideas were integrated in the Modern Synthesis.
What are Darwin’s ‘two great insights’?
- Descent with modification
- Natural selection as a mechanism for evolution.
These insights were supported by evidence from various fields such as geology and comparative anatomy.
What is methodological naturalism?
Methodological naturalism is the principle that scientific inquiry should rely on natural causes and explanations without invoking supernatural elements.
It is fundamental for hypothesis-based science.
What are some early ideas about the age of the Earth?
Ideas included:
* Catastrophism
* Uniformitarianism
* Geological time scales.
Understanding the Earth’s age is crucial for evolutionary theory as it provides a timeline for species development.
What is a scientific hypothesis?
A scientific hypothesis is a testable statement that predicts a relationship between variables.
Hypotheses are foundational to the scientific method.
What are the components of natural selection?
Components include:
* Variation in traits
* Heritability
* Differential survival and reproduction.
These components lead to evolutionary changes in populations over time.
What is an adaptation?
An adaptation is a trait that enhances the survival or reproduction of an organism in its environment.
Adaptations can arise through natural selection.
What is a norm of reaction plot?
A norm of reaction plot illustrates how a phenotype varies with changes in the environment, with genotype on one axis and environmental conditions on the other.
It helps to understand genotype-environment interactions.
What is the difference between phylogenies and pedigrees?
Phylogenies represent evolutionary relationships among species, while pedigrees depict genetic relationships within a family.
Phylogenetic trees are often used in evolutionary biology.
What are the types of phylogenetic trees?
Types include:
* Cladograms
* Phylograms
* Chronograms.
Each type represents evolutionary relationships differently, particularly in terms of branch lengths.
What is a synapomorphy?
A synapomorphy is a shared derived trait used to determine evolutionary relationships in cladistics.
Synapomorphies help identify monophyletic groups.
What are the limitations of various methods for building phylogenetic trees?
Limitations include:
* Long-branch attraction
* Incomplete data
* Errors in sequence alignment.
These factors can lead to inaccurate representations of evolutionary relationships.
What is the difference between particulate and blending inheritance?
Particulate inheritance involves discrete units (genes) being passed on, while blending inheritance suggests traits mix together.
Particulate inheritance allows for greater genetic variation in populations.
What is epigenetic inheritance?
Epigenetic inheritance refers to heritable changes in gene expression that do not involve changes to the underlying DNA sequence.
These changes can be influenced by environmental factors.
What does it mean for the genetic code to be redundant?
The genetic code is redundant because multiple codons can code for the same amino acid.
This redundancy provides a buffer against mutations affecting protein function.
What types of mutations exist?
Types of mutations include:
* Synonymous
* Non-synonymous
* Frameshift
* Nonsense mutations.
Each type can have different effects on gene function and organism fitness.
What is polyploidy?
Polyploidy is the condition of having more than two complete sets of chromosomes.
It is common in plants and can lead to speciation.
True or False: Natural selection can only act on heritable traits.
True
Only traits that can be passed from one generation to the next are subject to natural selection.
