Navigation Flashcards
What is kinesis? What is an example?
Non-directional movement caused by stimuli (change in speed or turning frequency)
Ex: High humidity causes rolly-pollies to go slow with lots of turns. Low humidity causes rolly-pollies to go fast and less amount of turns.
What is taxis? What is an example?
Directional movement lead by stimuli (orientation and navigation)
Ex: Moths drawn to a lightbulb
What are the four techniques of orientation to a specific location?
Beacon, piloting, dead reckoning, true navigation
What are some reasons that animals need to navigate?
Mating reasons, food, abiotic factors (WINTER IS COMING)
What is the beacon technique?
See place, go to place
Ex: AU football stadium. See it. Go to it
What is the piloting technique?
Uses a series of landmarks to get to a location
Ex: Go to Toomer’s corner and then look for the McDonald’s and Skybar will be next to it
What is the dead reckoning technique?
Organism has a compass, odometer, path integrator
Ex: If animal heads out to one place and saves that information into brain and then can find its way back based off that information.
What is the true navigation technique?
Animal has map and compass and can get to new places. Only a few animals have this.
What are the many methods of navigation?
Visual cues/landmarks, magnetic fields, chemical navigation, solar navigation, star navigation
What are visual cues/landmarks (example, too), and what are the downsides?
Often requires memory. Digger wasps make a circle with pinecones around their nests and will remember this landmark in order to find home. If you change the shape, they won’t go there.
Downsides: Rainstorms and wind can alter visual cues. Also need a memory to retain where they live.
What are magnetic fields (example, too), and what are the downsides?
Turtles use Earth’s magnetism in order to know where they will lay their eggs.
Downsides: Solar flare can alter Earth’s magnetic composition temporarily (breaching whales are victims of this) and North and South poles can flip.
What is chemical navigation (example, too), and what are the downsides?
Orchid bees collect a bouquet of scents to attract females. Salmon imprint on the stream where they were born and come back later in life.
Downsides: Pollutants or solar rays can impact chemical signatures. Losing a nose. Also, a sensitive sensor (especially for salmon) in oceans when they need to find a far away stream.
What is solar navigation (example, too), and what are the downsides?
Organisms will use the sun’s position and polarized light. Insects use polarized light even when the sun is not visible.
Downsides: Got to be able to see the sun (eyes could be harmed), need to have a sense of time (because sun is in different positions at different times of the day), solar eclipse, super cloudy conditions.
What is star navigation (example, too), and what are the downsides?
African dung beetles use the stars and moon to orient themselves. The milky way is a huge visual beacon.
Downsides: Only at night, need clear sky, and there’s light pollution
What are the costs and benefits of migration?
Costs: Use up energy, could end up somewhere wrong, new predators, maintaining two homes, how do you know when to go?
Benefits: More resources, better living conditions at different times of year (including better resources, temperature is better, better place for young to live), and reproduction reasons
