Lecture 9 - Lecture 9 How winter-active endothermic animals...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Lecture 9 How winter-active endothermic animals avoid freezing from last class.- On cold days animals can BASK in the sun to try to stay warm o Basking can be done while sleeping o Turtles bask on logs and rocks- Shivering is an important means of THERMOGENESIS o Black-capped Chickadees lower their body core temperature by 12 o C. There is a less gradient and less heat is lost. However, bird cannot stay awake and enter a deep sleep called TORPOR (12hrs)- Other animals become inactive (dormant) – ie. Mink frog - For many animals, a body temperature of below zero is fatal (ie. Snakes because they are ECTOTHERMS) o They survive by FREEZE AVOIDANCE in a HIBERNACULUM (crack in the earth, so they are below the frost line)- All turtles (and bullfrogs) escape sub-zero temperatures by going to the bottom of ponds and lakes o American Toads (and many salamanders) dig beneath the frost line- But insects and other invertebrates for dormant ABOVE the frost line (ie. woolly bear caterpillars) o...
View Full Document

This note was uploaded on 10/20/2011 for the course BIOL 1902 taught by Professor Runtz during the Fall '08 term at Carleton CA.

Page1 / 2

Lecture 9 - Lecture 9 How winter-active endothermic animals...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online