Species Concept
A group of similar organisms that normally interbreed in nature to produce _____
fertile offspring.
Allopatric speciation occurs after a population becomes ________ isolated.
geographically
Define Prezygotic Isolation Mechanisims
biological or behavioral barriers that prevent different species from interbreeding and forming a zygote (fertilized egg).
Define Macroevolution
Large, irreversible changes in the gene pool over a long period of time
Define Extinction
part of the life cycle of most species and plays a vital role in evolution.
What is allopatric speciation?
The type of speciation that occurs when a population is physically separated by a mountain or river.
in an Allopatric Speciation why do populations become geographically isolated?
Mountain buildings, change in sea levels, or changes in river direction
These mechanisms act before the egg is fertilized and include:
Temporal, Behavioral, Structural anatomy, and Gamete Incompatability
Macroevolution leads to evolutionary changes within a ____?
Species
What happens when a species becomes extinct?
its niche then becomes available to another species.
T or F
The traits or characteristics within a cline can change across a range
True
What is it called when it is also possible for a new species to arise without geographical isolation?
Sympatric Speciation
Give me an example of Behavioral related species
Elephants locking trunks, Nest building in sparrows, Flap dance in the Blue-footed Bobby
What are the six patterns in Macroevolution
Gradualism and Punctuated Equilibrium
Extinction
Divergent evolution and Adaptive Radiation
Parallel Evolution
Convergent evolution
Coevolution
habitat destruction, Climate Change, Coexistence
What are the three different types of Speciation?
Allopatric Speciation
Sympatric Speciation
Instantaneous Speciation
Over time, genetic differences develop, which leads to the two populations becoming __________
Reproductively Isolated.
Give an example of Temporal related species
13-year and 17-year cicadas
Give me an example of Macroevolution
Transition from dinosaurs to birds, evolution of whales and dolphins, e.t.c
Why has extinction accelerated?
intense human activities over the last 100–500 years.
What do Reproductive Isolating Mechanisms operate?
Before fertilization and After fertilization
Comprehension Check
Which type of Speciation?
Two different types of three-spined stickleback fish (Gasterosteus aculeatus) are found in the lakes of British Columbia, Canada.
The larger of the two types feed on prey near the water’s edge while the smaller one feeds on plankton in the open waters.
These fish originally had a common ancestor, but the two types are currently not considered different to be species even though they are reproductively isolated.
Sympatric speciation
In coral reefs, gamete incompatibility prevents ____?
the formation of numerous inter-species hybrids.
Whats another name for a formation of a new species
Speciation
Why is habitat destrution the main reason for extinction?
it directly eliminates the essential resources food, water, shelter, and breeding grounds that species need to survive.