The Regulation of Ant Colony Foraging Activity without Spatial Information

1. The Regulation of Ant Colony Foraging Activity without Spatial Information Balaji Prabhakar, Katherine N. Dektar, Deborah M. Gordon Presented by Zhiyuan Chen

2. Outlines • Biology Background • Computer Science Modeling • Biology Interpretation

3. Outlines • Biology Background • Computer Science Modeling • Biology Interpretation

4. Ant Social Insects

5. Ant Social Insects Collective behavior without central control

6. Ant Social Insects Collective behavior without central control Local interactions among individuals

7. How do actions of individuals add up to the collective behavior of animals?

8. Ant Foraging Pheromone trail (Spatial Information)

9. Ant Foraging Pheromone trail Without pheromone trail

10. Ant Foraging Pheromone trail Without pheromone trail

11. How do red harvester ant forage?

12. Red Harvester Ant Foraging Returning forager Outgoing forager

13. Red Harvester Ant Foraging Returning forager Outgoing forager R1 O1 O2 Ant Colony

14. Red Harvester Ant Foraging Returning forager Outgoing forager R1 O1 O2 Ant Colony

15. Red Harvester Ant Foraging Returning forager Outgoing forager R1 O1 O2 Ant Colony

16. Red Harvester Ant Foraging Returning forager Outgoing forager R1 O1 O2 Ant Colony

17. Red Harvester Ant Foraging Returning forager Outgoing forager R1 O1 O2 Ant Colony

18. Red Harvester Ant Foraging Returning forager Outgoing forager R1 O1 O2 Ant Colony

19. Return Rate vs. Outgoing Rate #Returning forager per second #Outgoing forager per second

20. Return Rate vs. Outgoing Rate Hypothesis Return Rate 90% Successful Food Availability Outgoing Rate

21. Modeling Problems Model the return process of returning foragers. Compute outgoing rate based on returning rate.

22. Data 62 trials 13 distinct mature colonies Video film length: 0 – 1200 sec 240 – 420 sec: prevent returning foragers

23. Outlines • Biology Background • Computer Science Modeling • Biology Interpretation

24. Can we model the return process of returning foragers?

25. Can we model the return process of returning foragers? Answer: Poisson Process

26. Poisson Process Stochastic process Number of arrivals in a time interval The time of these arrivals in a time interval

27. Poisson Process Example Cars entering a highway #Cars entering a highway in an hour The time of these enterings in an hour

28. Poisson Process Assumptions Decision to enter the highway is independently made by each car driver

29. Poisson Process Assumptions Decision to enter the highway is independently made by each car driver t1 t2 t3

30. Poisson Process Property N(t): #Arrivals in interval (0, t] N(t) is Poisson distribution

31. Poisson Distribution Average #arrivals/hour

32. Poisson Distribution

33. Poisson Process Property

34. Return of Returning Foragers

35. The return process of returning foragers can be modeled as Poisson Process.

36. Can we compute outgoing rate based on returning rate? Can we predict #outgoing foragers at a particular time n?

37. Computing Outgoing Rate )

38. Computing Outgoing Rate ) #Returning foragers of time n-1 #Outgoing foragers of time n-1 Outgoing Rate of time n

39. Computing Outgoing Rate ) #Returning foragers of time n-1 #Outgoing foragers of time n-1 Outgoing Rate of time n

40. Computing Outgoing Rate ) #Returning foragers of time n-1 #Outgoing foragers of time n-1 Outgoing Rate of time n

41. Computing Outgoing Rate ) #Returning foragers of time n-1 #Outgoing foragers of time n-1 Outgoing Rate of time n

42. Computing Outgoing Rate ) #Returning foragers of time n-1 #Outgoing foragers of time n-1 Outgoing Rate of time n

43. Computing Outgoing Rate ) #Returning foragers of time n-1 #Outgoing foragers of time n-1 Outgoing Rate of time n

44. Computing Outgoing Rate )

45. Predicting #Outgoing Foragers )

46. Return of Returning Foragers Red: RR (Observed) Blue: OR (Observed) Green: OR (Predicted)

47. Return of Returning Foragers

48. Return of Returning Foragers Return

49. Outlines • Biology Background • Computer Science Modeling • Biology Interpretation

50. Return Rate vs. Outgoing Rate Return Rate Food Availability Outgoing Rate