1. Environmental signals Resource recruitment signals –Costs and benefits –Types –Examples Predator detection signals –Types –Examples

2. Give Game

3. Why signal food location? Costs –Increases competition –Signal production takes time and energy Potential Benefits –Increasing number of foragers improves foraging success and/or decreases predation risk –Increases reproduction of relatives –Food may allow long-term survival of group which increases chance of discovering sites in future

4. Types of location signals Discoverer broadcasts signal from the resource and receivers recruit to the site Discoverer goes to receivers (often at nest or colony), communicates discovery, and then leads receivers to site Discoverer goes to receivers and provides directional information about site

5. Ravens recruit to carcasses

6. Cliff swallow recruitment calls

7. Food signalling by osprey Males give display to females after catching preferred fish

8. Rhesus macaque food calls

9. Chimpanzee pant-hoots Pant-hoots advertise discovery of divisible food and are given by males Grunts are given for any amount of preferred food

10. Mole rats recruit to roots

11. Food recruitment in ants

12. Food recruitment in honey bees: dance angle indicates direction

13. Dance duration indicates distance

14. Dance divergence indicates patch size

15. Advertisement distance is constrained by dance duration

16. Bee dialects reflect foraging distances

17. Azimuth encoding in bee dances

18. Summary of food-associated signals Vertebrates: Food signalling is rare. Most signals occur at food (except mole-rats) Social insects: Food signalling is common. Signals to food from hive using pheromones or “language”

19. Predator alarm signals Cause –Alert conspecifics –Deter predator Types –Low risk - elicit scans –Predator inspection and mobbing signals –High risk - prompts escape –Distress signals

20. Private alarm calls

21. Benefits of alarm calls

22. Ground squirrel alarm calls

23. Alarm calls do not coordinate movements

24. Alarm calls differ by age and sex

25. Alarm calls and kinship

26. Referential signalling Do alarm calls convey information about predator type or just urgency associated with potential attack?

27. Vervet alarm calls

28. Alarm calls refer to predators

29. Development of vervet alarm calls

30. Vervet calls, relatedness and dominance

32. Meerkat alarm calls signal predator class and urgency

33. Intertrophic level signalling Detection notification signals Condition notification signals Aposematic signals Distress signals

34. Predator notification displays

35. Aposemitism Prey advertise taste to predators Initial evolution requires kin groups Can be invaded by mimics, but must remain at low frequencies