KEEP THIS IN MIND
•  Microclimates determine local
conditions
A CLASSIFICATION
Body Temp
•  Poikilotherms and Homeotherms
5
10
15
20
Environment Temperature
ENVIRONMENTAL
IMPACTS
•  Gains
Losses
SUN
RESPIRATION
WIND
AIR
GROUND
GROUND
REMEMBER
•  Biochemical reaction rates are
temperature dependent
A LAW
Reaction Rates
•  Van’t Hoff’s law: Reaction rates double
every 10 C
Temperature
A THOUGHT
•  Enzyme reaction rates can affect many
processes including development,
physiology, behavior, etc.
BARK BEETLE RESIDENCE
TIME
TEMP.
Male
Female
15
20
25
30
32
35
85
32
12
9
8
8
82
32
11
9
8
9
ATTACK RATE
TEMPERATURE EFFECTS
ON PARASITIC WASPS
TEMPERATURE
TEMPERATURE EFFECTS
4
3.5
3
2.5
2
1.5
1
0.5
0
0
10
20
T em p er a t u r e
30
40
DEVELOPMENTAL TIME
STORED PRODUCTS
BEETLES
TEMPERATURE
TEMPERATURE AND DEVELOPMENT RATE
HOW DO POIKILOTHERMS
DEAL WITH EXTREMES?
•  COLD:
•  Super cooling is cooling of a liquid
below its freezing point without it
becoming solid. •  Freezing point depression is cooling
below freezing point of a pure liquid
due to a solute e.g. NaCl
Ex: PAINTED TURTLES
•  Hatchling painted turtles typically
remain inside their shallow (8–14 cm)
nest throughout their first winter where
temperatures often drop to -10C
•  Their skin resists ice
nucleus penetration
Ex: GALL MOTHS
•  Freezing point depression through
synthesis of antifreeze (glycerols)
HEAT SHOCK PROTEINS
ANOTHER OPTION
•  Maybe you should just leave
IMPACT OF GLOBAL
WARMING
Bergant et al. 2005
The future?
“In a future with increased mean temperatures … heat waves would become more intense, longer las:ng, and more frequent .” WHY DOES GLOBAL
WARMING MATTER?
•  Both mean and variance can both
affect ecological processes
A CONCEPT
•  For poikilotherms, time is temperature
dependent but for homeotherms it is
not
A QUESTION
•  Q: How do insectivorous birds
determine when the best time to breed?
•  A: They use calendars (photoperiod)
A PROBLEM
•  For insects, timing depends upon time
and temperature
AN IMPACT
•  Mismatch timing can be important
Year!
Year!
A BIGGER PROBLEM
•  For long-distance migrants there is no
way to anticipate changes in timing in
a given year
Swamp
Forest
WHAT ABOUT HEAT
WAVES?
•  They will cause continuous stress
•  Many animals and plants cannot escape
these stresses
MICRO HABITATS CAN
VARY DRAMATICALLY
•  Position on a rock can be critical for a
mussel on a rock