Miscellaneous
defined as a group of populations whose members have the potential to interbreed and produce fertile offspring
Species
The scientific theory stating that living species are descendants of ancestral species that were different from present day ones
Evolution
the imprints or remains of organisms that lived in the past
Fossils
Scientists compare fossils from different time periods to document differences between
past and present organisms
the mechanism for evolutionary change
Natural Selection
refers to how well an individual can survive and reproduce in its environment
Fitness
are remnants of features that served important functions in the organism’s ancestors
Vestigial Structures
Similarities in the ________ of various organisms provide a strong argument in favor of the genetic connectedness of different animal groups
embryos
individuals do not evolve. Rather, it is the _________ that evolves over time
individuals do not evolve. Rather, it is the population that evolves over time
inherited traits that help the organism survive and reproduce in its environment
Adaptations
anatomical similarities in different organism
Darwin cited the anatomical similarities among vertebrate forelimbs as evidence of common ancestry
Homologous Structures
When two different species do interact with each other, __________ isolation prevents genetic exchange and maintains a boundary between species
reproductive
The two post zygotic barriers are
Reduced hybrid viability
Interaction of parental genes impairs the hybrid’s development or survival
Reduced hybrid fertility
Hybrids survive but can not produce viable offspring
the process by which one species splits into two or more species
Speciation
Give an example of a vestigial structure
Human tail bone
Whale pelvic bone
Snake hind limbs
A key event in the origin of many new species is the physical separation of a population from other populations of the same species
Allopatric or Geographic Speciation
What is temporal Isolation?
Breed at different times or seasons
prevent mating or fertilization between species
Prezygotic Barriers
What structure do all embryos have but humans get rid of through development in the womb?
Gill Slits
There can be both ___________ (before a zygote is formed) or ________________ (after a zygote is formed) barriers that prevent interbreeding
1. Prezygotic
2. Postzygotic
Name 3 of the 5 types of Prezygotic Barriers
Habitat isolation
Organisms living in different places
Temporal isolation
Breed at different times or seasons
Behavioral isolation
Mating rituals are different
Mechanical isolation
Physical incompatibility of reproductive parts
Gametic isolation
Molecular incompatibility of eggs and sperm