Lecture 12

Question 1

What are the advantages of using thermometry to measure body temperature of birds and mammals?

Answer 1

Quick, low-cost, core temperature measurement

Question 2

What are the disadvantages of using thermometry to measure body temperature of birds and mammals?

Answer 2

Single point measurement, difficult to make on freely moving animals. Stress responses may influence body temperature.
Need to capture the animal

Question 3

What are the advantages of using implanted data loggers to measure body temperature of birds and mammals?

Answer 3

Measurement of internal temperature(s) over many months/ years. Can be combined with other sensors e.g. heart rate
Continuous

Question 4

What are the disadvantages of using implanted data loggers to measure body temperature of birds and mammals?

Answer 4

Surgical constraints, most cases require recapture for data recovery. Data logger size limitations.
Capture and surgery.

Question 5

What are the advantages of using radio transmitters: implanted to measure body temperature of birds and mammals?

Answer 5

Measurement of internal temperature(s) that can be remotely recorded.
Continuous

Question 6

What are the disadvantages of using radio transmitters: implanted to measure body temperature of birds and mammals?

Answer 6

Measurement duration limited by battery power. External receiver or manual data logging system required for continuous recording.
Capture, surgery.

Question 7

What are the advantages of using radio transmitters: skin surface to measure body temperature of birds and mammals?

Answer 7

Remote measurement of skin temperature. Easily attached by glue. Continuous

Question 8

What are the disadvantages of using radio transmitters: skin surface to measure body temperature of birds and mammals?

Answer 8

Skin temperature is influenced by environmental conditions as well as physiological parameters. Signal noise increased by movement. External devices increase drag.
Capture

Question 9

What are the advantages of using gastrointestinal devices to measure body temperature of birds and mammals?

Answer 9

Deployment by feed tube/ ingested. Continuous recording of internal temperature. Detection of prey/ food intake.
Continuous

Question 10

What are the advantages of using non-surgical implants, e.g. rectal, aural, vaginal to measure body temperature of birds and mammals?

Answer 10

Internal temperature measurement avoiding surgery.

Continuous

Question 11

What are the disadvantages of using non-surgical implants, e.g. rectal, aural, vaginal to measure body temperature of birds and mammals?

Answer 11

Temporary measurement of body region may constrain biological function and limits measurement duration

Question 12

What are the advantages of using faecal temperature to measure body temperature of birds and mammals?

Answer 12

Non-invasive proxy of rectal temperature (no capture, no surgery)

Question 13

What are the disadvantages of using faecal temperature to measure body temperature of birds and mammals?

Answer 13

Calibration of rectal temperature with faecal temperature required. Temperature prone to vary with environmental conditions

Question 14

What are the advantages of using PIT tags to measure body temperature of birds and mammals?

Answer 14

Low-cost, minimally invasive, multiple discrete measurements, avoiding recapture. Temperature measurement possible throughout the life of organism

Question 15

What are the disadvantages of using PIT tags to measure body temperature of birds and mammals?

Answer 15

Non-continuous measurement limited by RFID receiver placement. Reading range restricts measurement to close proximity. Migration of tag in some cases.
Capture

Question 16

What are the advantages of using IR thermography to measure body temperature of birds and mammals?

Answer 16

Remote, non-invasive, sampling with high spatial and temporal resolution. Thermal video allows temperature measurement of discrete behaviours.
Continuous

Question 17

What are the disadvantages of using IR thermography to measure body temperature of birds and mammals?

Answer 17

Influenced by environmental conditions and may not clearly reflect internal temperature. Continuous recording of thermal video over several hours may be limited by memory. Arrival must be within field of view of researches/ camera

Question 18

What are the advantages of using IR thermometry to measure body temperature of birds and mammals?

Answer 18

Remote, non-invasive recording of surface temperature.

Low-cost

Question 19

What are the disadvantages of using IR thermometry to measure body temperature of birds and mammals?

Answer 19

Spatial resolution limited by increasing measurement area with distance. Typical distances of 1-5m

Question 20

What are the advantages of using temperature-sensitive paint to measure body temperature of birds and mammals?

Answer 20

Rapid assessment of temperature range of surface by colour change

Question 21

What are the disadvantages of using temperature-sensitive paint to measure body temperature of birds and mammals?

Answer 21

Low accuracy and resolution. Toxicity and visual marking may affect health/ behaviour/ predation risk.
Capture

Question 22

What are the effects that temperature have on the rate of biological processes (because it effects chemical processes)? What do these effects therefore mean?

Answer 22

1. Rate-enhancing effects-mainly a consequence of temperature on enzyme function
2. Destructive effects (normally outside the range of temperatures experienced)-denaturing of enzymes, disruption of cell membranes etc.
3. There is therefore an optimum temperature

Question 23

What are the factors affecting heat transfer in animals?

Answer 23

. Surface area
. Temperature difference (reduce temp difference then there is a reduction in the rate in which heat is transferred)
. Specific heat of conductance (so how well insulated it is, so how is it at aiding it reducing heat transfer)

Question 24

What does adding heat (energy) to a body or losing it cause?

Answer 24

. Adding heat (energy to a body causes its temperature to rise)
. Conversely, losing heat causes the temperature to fall

Question 25

Give an equation for body heat

Answer 25

Body heat= Heat produces (MR) + Heat transferred

Question 26

Explain how this body heat equation: Body heat= Heat produced (MR) + Heat transferred Differs in ectotherms and endotherms

Answer 26

In ectotherms the heat produced is low compared to heat that is transferred so essentially any heat that they produce is lost. An endotherms basically tries to keep this as a balanced equation so that body temperature stays constant

Question 27

What are the physical processes involved in heat transfer?

Answer 27

``` . Conduction . Convection . Radiation . Evaporation . Heat storage ```

Question 28

What happens if you increase or decrease heat storage in an animal?

Answer 28

Then you increase heat store then you increase the whole temperature of the system and if you reduce heat storage then you will reduce it provided everything is in balance

Question 29

What are the ways in which animals are transferred heat?

Answer 29

``` . Metabolic heat generation . Direct solar radiation . Radiation . Thermal radiation from atmosphere . Thermal radiation . Reflected light ```

Question 30

What are the ways in which heat is transferred from an animal?

Answer 30

. Conduction (so laying down) . Evaporation (thermal radiation to the sky) . Convection . Radiation

Question 31

When do you get conduction as a way of heat transfer from an animal? How is there convection in this case?

Answer 31

Where the animal is in contact with a substrate and is there is a direct transfer of heat. There is convection by the fluid median in this case the gas/ air

Question 32

What is the rate of flow of heat transfer directly related to in conduction?

Answer 32

To the temperature difference plus the thickness of the surface plus the surface area which is in contact

Question 33

What is the highest barrier of heat conductance (so insulation)

Answer 33

Still air

Question 34

Why does fur thickness increase insulation?

Answer 34

Because of the air that is trapped within that fur

Question 35

What is convection?

Answer 35

The flow of heat between two bodies by the mass movement of an intervening fluid (gas or liquid)

Question 36

What is heat flux density?

Answer 36

It is the rate at which heat is transferred

Question 37

What is heat flux density linked to? So what does this tell us?

Answer 37

Is linked to thermal heat conductivity of the median plus the effective boundary layer plus that temperature difference so can see that temperature difference is an important component not just to conduction but also of convection.

Question 38

What is ‘the boundary layer’?

Answer 38

Is the effective layer that is around a body where there is effectively still air or still water

Question 39

One of the adaptions of marine animals is to trap a layer of water next to the skin, what two things does this aid? So what does this mean if there is an increased boundary layer?

Answer 39

. It increases the effective boundary layer so decreases convection . Also provides a reduced friction layer . So as thermoregulation increases an increased boundary layer means that there is a reduced heat transfer

Question 40

What is radiation?

Answer 40

Energy emitted by all bodies whose temperature is >-273 degrees Celsius

Question 41

What is radiation directly related to?

Answer 41

The temperature difference

Question 42

What 3 things regulate body temperature in ectotherms?

Answer 42

. Morphology . Behaviour . Physiology