Evolution Flashcards
Evolution
The process of cumulative change in the heritable characteristics of a species.
Discuss the evidence for evolution in terms of the fossil record
Fossils provide evidence of extinct species and the transition of species over time, showing a pattern of increasing complexity
Discuss the evidence for evolution in terms of selective breeding
Demonstrates that specific traits can be amplified or eliminated through controlled breeding, highlighting the potential for evolutionary change
Discuss the evidence for evolution in terms of homologous structures
Similarities in anatomical structures among different species suggest a common ancestry and the modification of existing traits
Discuss the evidence for evolution in terms of DNA Evidence
Comparing DNA sequences of different organisms reveals genetic similarities that indicate shared ancestry
Explain the “Survival of the fittest” in the context of natural selection.
In natural selection, individuals within a population exhibit variation in their traits:
1. Reproductive advantage
2. Better camouflage
3. Enhanced ability to find food
4. Resistance to diseases
Define “Survival of the fittest”
Individuals with advantageous traits or adaptions are more likely to survive and reproduce, passing those traits on to future generations.
Outline where genetic variation comes from in terms of mutation
Changes in the DNA sequence that occur spontaneously or due to environmental factors
Outline where genetic variation comes from in terms of genetic recombination
The mixing and shuffling of genetic material during sexual reproduction
Outline where genetic variation comes from in terms of gene flow
The transfer of genes between populations through migration and interbreeding.
Describe how natural selection led to the evolution of peppered moths
Prior to the Industrial Revolution, peppered moths in England had
predominantly light-coloured wings, which provided effective camouflage
against light-coloured tree bark
As industrial pollution darkened the tree trunks, a variant of the peppered
moth with dark wings become more advantageous for camouflage.
Natural selection favoured the dark winged moths, as they were better
able to evade predators and survive to reproduce
Describe how natural selection leads to the evolution of antibiotic resistance
When antibiotics are used to treat bacterial infections, they selectively kill
susceptible bacteria, but some individuals may possess genetic mutations that confer resistance to the antibiotic
These resistant bacteria survive and reproduce, passing on their resistance
genes to subsequent generations
Over time, the population of bacteria becomes dominated by individuals
with antibiotic resistance, making the treatment less effective.
Natural Selection
Organisms that are more adapted to their environment are more likely to survive and pass on the genes that aided their success.
