Adaptations, Variations & Mutations
A structure, behaviour, or physiological trait that helps an organism survive in its environment.
What is an adaptation?
The process where individuals with favourable traits survive and reproduce more.
What is natural selection?
These preserved remains or traces of organisms reveal that species appear and disappear over time.
What are fossils?
All the alleles in a population together make up this.
What is the gene pool?
The formation of new species from existing ones.
Differences among individuals in a population, which may be structural, functional, or physiological.
What is variation?
When humans choose which organisms breed in order to produce desired traits.
What is artificial selection?
This scientist’s theory of uniformitarianism influenced Darwin by suggesting the Earth was far older than 6000 years.
Who is Charles Lyell?
A change in the frequency of an allele in a population.
What is microevolution?
A pre-zygotic mechanism where species mate in different habitats.
What is habitat isolation?
A change in DNA that introduces a new allele into a population; sometimes caused by radiation or chemicals.
What is a mutation?
The ability an organism has to reproduce viable offspring, ultimately contributing to the gene pool of the next generation.
Lamarck’s idea that traits gained during life could be passed on to offspring.
What is inheritance of acquired characteristics?
Name one of the five factors that cause evolutionary change
What is mutation/ gene flow/ non-random mating/ genetic drift/ natural selection?
A post-zygotic barrier where hybrids survive but cannot reproduce.
What is hybrid sterility?
A genetic advantage that helps an organism survive environmental change (like heat-tolerant Daphnia).
What is a selective advantage?
Two disadvantages of artificial selection.
What is decreased genetic diversity, increase of harmful traits, etc.?
Structures that are similar in origin but different in function (e.g., human arm, bat wing).
What are homologous structures?
This type of natural selection favours averages and reduces variation in a population.
What is stabilizing selection?
Speciation that occurs when populations become geographically separated.
What is allopatric speciation?
This example that we studied in class demonstrated how changes in the environment alter which traits are favoured by natural selection.
What is the English peppered moth case?
The evolution of antibiotic-resistant bacteria demonstrates this concept in species that reproduce rapidly.
What is selective advantage through mutation? or What is natural selection?
This type of fossil shows intermediary forms between ancient and modern species.
What is a transitional fossil?
Competition for mates leads to traits like peacock feathers; males and females often differ.
What is sexual selection?
Darwin’s finches are a famous example of this evolutionary pattern, where one ancestor gives rise to many species.