Two broad categories of behaviors are Proximate and Ultimate behaviour. The presentation gives a brief introduction on Proximate and Ultimate causes of behaviour

1. Dr. Surjya Kumar Saikia
Department of Zoology
Visva-Bharati
Proximate vs. Ultimate
Causes of Animal Behavior

2. Expected outcomes
• Able to understand proximate and ultimate causes of behavior
• Able to identify which behavior is proximate and which is ultimate

3. 1. Proximate vs. Ultimate Causes
2. Genetic Component + Environment Influence
3. Natural Selection favors behaviors that
increase survival and reproductive success

4. IT ISVERY MUCH ESSENTIALTO KNOWTHE
ACTUAL CAUSE OFTHE BEHAVIOR…..
Animal
Behavior
Proximate
cause
Ultimate
cause

5. Proximate
Cause
•Physiological meachanisms
Ultimate
cause
•Evolutionary goal

6. Looking for the cause……
Those that explore how the behavior contributes to
survival and reproduction
Two questions are common,
Those that focus on the immediate stimulus and
mechanism for the behavior
1
2

7. Ultimate, or “why,” questions about behavior
Address the evolutionary significance of a behavior
1
2
Proximate, or “how,” questions about behavior
• Focus on the environmental stimuli that trigger a behavior,
• Focus on the genetic, physiological, and anatomical mechanisms underlying a
behavioral act

8. Example of Proximate stimuli
Proximate causes
External stimuli- changes in day length
Internal stimuli - hormone levels

9. Example of Proximate stimuli

10. pikrepo
Animals stay in herd is Ultimate cause of behavior

11. pixabay
Bird migration is an example of Ultimate causes of behavior

12. Bird migration is an example of Ultimate causes of behavior

13. Example of Ultimate causes
Birds that migrate have a selective advantage
over non-migratory birds over time; and such
migration could be due to long term climate
changes, glaciation, diseases, taking advantage
of food sources, mating etc.