migration Flashcards
Name two different reasons for migration.
- station keeping- individuals will travel around the territory to lay scent marks.
- ranging dispersal- new territories are found with new conspecifics to breed with and to foraging in
Why is migration always directional and purposeful?
Energy is wasted if it is not.
Why does migration normally occur in large groups.
It is intimidating to predators, it gives a larger number of individuals to watch the predators and it gives more choice repaired it is the hunt which protects the numbers on the whole.
How can migration be triggered.
By environmental factors and by social ones such as the heart becoming too large to sustain itself.
How can hatchlings of migratory birds be used to argue the benefits of migration?
when crossbred with non-migratory birds, the progeny had a mixed restlessness during migratory season. this shows the characteristics are both beneficial to the respective species.
what is migratory syndrome
When a species has phenotypic characteristics to aid migrationWhen a species has phenotypic characteristics to aid migration
What is the difference between navigation and orientation
Navigation is directional trouble with no sensory cues while orientation is the directional travel using sensory cues.
what is a diadromous fish?
one that travels to different water conditions to spawn.
what is anadromous
when a salt water fish spawns in fresh water
what is catadromous
when a fresh water fish spawns in sea water
what is to and from migration
trips that occur between two points
what us round trip migration
similar to to and fro but stops are made along the way.
what is loop migration?
different routes sed oil the way to and back from destination.
what is one-way migration?
multiple generations complete the loop
