Extreme Biology Flashcards
What are the unusual properties that make earth habitable?
The earth is tilted on its axis meaning it has seasons and different daylight hours- likely caused by a collision. This has given the earth different biomes.
Earth has a low temperature, low surface pressure.
Why do some animals migrate south in the winter?
The north gets very cold in the winter and gets lots of snow, this snow freezes over resources. Animals will travel south to avoid the poor resource period and travel back up to take advantage of the rich resources in the summer.
What are the different types of migration?
- Obligate annual migration: happens annually usually to the same location
- Irruptive migration: species move when conditions get too bad to survive but will stay if conditions allow it.
- Partial migration: half the population migrate but half stay e.g. juveniles and adults. This pattern is fairly regular annually, regardless of conditions.
What is sheltering?
Some animals choose not to migrate, instead they burrow under the snow which creates an insulative layer. This area under the snow is called the subnivean zone and stays around 0 degrees. Some animals will burrow all winter and others will only burrow at night or through storms.
Which animals are unable to shelter?
Larger animals are unable to shelter, or large animals which need large territories to fulfill their energy demands.
How can fur or fat help animals conserve heat?
Different materials have different levels of conductivity, fur or fat are good insulators so trap heat inside the body.
What internal mechanisms can help animals conserve heat?
Vasoconstriction and vasodilation, raising fur to trap air, blubber in marine animals.
How do countercurrent systems work?
Countercurrent systems move warm and cold blood in opposite directions next to each other to allow heat to be transferred at all times they are running next to each other. This system can be found in the gills of a fish, the kidney, in the feet of birds to prevent heat loss.
