natural selection Flashcards
What is natural selection
The process whereby organisms better adapted to their environment tend to survive and produce more offspring.
Who theorised natural selection
Charles Darwin and Alfred Russel Wallace
Describe Lamarck’s theory
Physical changes in organisms during their lifetime—such as greater development of an organ or a part through increased use could be transmitted to their offspring.
Describe Darwin’s theory
Darwin stated that species adapt to their environment over time and change in accordance to
Name the four types of evidence we have to support the theory of evolution
Anatomy, Molecular biology, biogeography, fossils
Describe ‘variation’ in relation to evolution
Genetic variation is the presence of differences in sequences of genes between individual organisms of a species. It enables natural selection
Explain behavioural adaptations
Behavioural adaptations are the things organisms do to survive
What’s an example of a behavioural adaptation
Fish swim in schools for protection, dolphins do the same
What is a functional adaptation
A functional adaptation is a structure or behaviour that has arisen sometime in the evolutionary history of a species to aid in that species’, or its predecessors’, survival
Describe Physiological adaptations
Physiological adaptation is an internal body process to regulate and maintain homeostasis for an organism to survive in the environment in which it exists, examples include temperature regulation, release of toxins or poisons.
What are vestigial organs and provide an example
Remnants of lost functions that our ancestors possessed. They once represented a function that evolved out of a necessity for survival, but over time that function became non-existent. An example is wisdom teeth
Define Homologous
An organ or body part that appears in different animals and is similar in structure and location, but doesn’t necessarily share the same purpose.
Define Analogous
Features of different species that are similar in function but not necessarily in structure and which do not derive from a common ancestral feature
Define Speciation
Speciation is how a new kind of plant or animal species is created. Speciation occurs when a group within a species separates from other members of its species and develops its own unique characteristics
What is peppered moth and why does it relate to natural selection
Wing-color changes in peppered moths are a common example of what scientists refer to as natural selection. In it, organisms develop random mutations. Some of the gene changes will leave individuals better suited — or adapted — to their environment. These individuals will tend to survive more often.
