This creates variation within a population
mutation
This is the process where populations evolve into distinct species.
Speciation
This diagram shows evolutionary relationships between organisms.
A phylogenetic tree
This is the natural environment where an organism lives.
These are structures that are similar because species share a common ancestor.
Homologous structures
Organisms with traits best suited to an environment are considered this.
Fitness
A species is defined as organisms that can produce this type of offspring.
Fertile offspring
This point on a phylogenetic tree represents a common ancestor.
This describes the role of a species in its environment.
A niche
Monkey arms and bat wings are examples of this type of structure.
Homologous structures
This process causes beneficial traits to become more common over time.
Natural Selection
This causes populations of the same species to become different over time.
Selective pressures
Organisms sharing a more recent node are considered this.
More closely related
Different species in the African savannah survive together because they use different versions of this.
Niches/ resources
Homologous structures suggest species share this.
A common ancestor
Giraffes evolved long necks mainly to access this.
Food high in trees / leaves unavailable to other herbivores
Over many generations, mutations and natural selection can eventually create this.
A new species
The organisms at the tips of a phylogenetic tree are all considered equally this.
Evolved
This type of adaptation involves learned or instinctive actions.
A behavioral adaptation
Homologous structures may serve different purposes but have similar this.
Selective pressures are environmental factors that affect an organism’s ability to do these two things.
Survive and reproduce
If two organisms can no longer produce fertile offspring together, they are considered this.
Separate species
This term describes a group that contains a common ancestor and all descendants.
A clade
Usually only one species can occupy one of these at a time.
A niche
Small genetic differences can lead to large differences in this.
Appearance/ structure