The ecology of information use

1. The ecology of information use The reporter of section 3.1-3.3 : Yu Chi Lin The reporter of section 3.4-3.6 : Pei Chen Wu

2. 3.1 introduction • Information is involved in social decision, communication and selection of mates. • It can affect population structure as well as the distribution of animals over habitats. • Exploring quality estimation, pre-detection context, spatial memory, social learning and cultural transmission.

3. 3.2 Quality estimation • 3.2.1 Estimating time: scalar expectancy theory (SET) • 3.2.2 Estimating quality in unchanging environments: Bayesian models • 3.2.3 Tracking quality: linear operator models • 3.2.4 Estimating quality in social environments: using public information

4. 3.2.1 Estimating time: scalar expectancy theory (SET) • The ability to estimate short time intervalsis likely to be of survival value in a number of circumstances. • SET assumes that animals measure and memorize time elapsed (S)to a significant event. (i.e. food reward)

5. Variance and interval size • SET hypothesizes that the variance of the memorized distribution increases with the magnitude of S.

6. Starlings (sturnus vulgaris) foraging • Leaving sooner would have cost some prey, leaving later would have wasted time. • The greater variance observed for the shortest S may indicate a lower limit to the variability of remembered distribution.

7. Variability of experienced S • SET predicts preference for the variable alternative, assuming shorter delays are preferred.

8. 3.2.2 Estimating quality in unchanging environments: Bayesian models • What’s the Bayesian estimation? • Forming an estimate by the combination of current sample information acquired from the object and a prior expectation of object value distribution in the environment.

9. Consider three types of environment- prey underdispersed • Has the highest updated estimate of the number of prey remaining in the patch • Exploits the patch more extensively • Requires longer unrewarded search before its updated estimate declines to the threshold for patch abandonment

10. Consider three types of environment- prey overdispersed • The more successful member no longer predicted the order of patch departure nor the length of unrewarded search.

11. Consider three types of environment- prey dispersed independently • The best policy is to decrease the estimation with patch time irrespective of encounters.

12. 3.2.3 Tracking quality: linear operator models • Memory window models estimate over a range (window) of experiences, dropping the oldest events as new ones are added to the estimate. • Memory window models may be difficult to test. • Devaluating outdated information by the basis of linear operator learning rules. • The relative payoff sum (RPS) have been proposed by linear operator rules.

13. The RPS rule • P: the probability • t : the last trial • i : the option on trial t+1 • k: the all alternative • V: the value • is the probability of responding to option i on trial t+1.

14. How RPS updates estimates of Vi(t)? • Vi(t) = α Vi(t-1) + (1-α) ri + Qi(t) • α : the memory parameter (0<α<1) • t : the last trial • i : the option on trial t+1 • k: the all alternative • V: the value • Qi(t): the rewards obtained from alternative i during trial t • ri : Vi(0)

15. 3.2.4 Estimating quality in social environments: using public information • Using public information. • For a group of G individuals using public information can sample at up to G times the rate of solitary.

16. Experimental evidence of public information using • Starlings are social foragers and sample a food patch by probing their bill into the substrate. • Foraging with a partner, a subject samples more when paired with a low-information partner.

17. 3.3 Detecting cryptic prey: search image or search speed? • Tinbergen (1960) suggested that foragers confronted with cryptic prey develop a ‘search image’ that enhances their detection. • Search image hypothesis • Reduced search rate hypothesis • Dawkins (1971) cautions that alternative hypotheses can account for apostatic prey selection.

18. The experiments of the crucial prediction • Pigeons developed a search image that was specific to a single cryptic prey type at a time.

19. 3.4Spatial Memory • Food storage and retrieving • Neuroanatomical structure • Sex difference • A dedicated cognitive process OR simply improvement of general spatial information processing?

20. Food storing and retrieving • Paridae 山雀科 - titmouse 山雀, chickadee 北美山雀 • Corvidae 鴉科 - jay 松鴉/堅鳥, nutcracker 星鳥 • Food was stored in hundreds of sites that were never re-used. Over a period of time, they re-visit the sites to feed. • Monocular occlusion experiment • Ex. Marsh tit - Fail to recover stored food when a different eye is available.

21. Tit mouse (tit) Chickadee Pinyon jay Clark’s Nutcracker

22. Specialized neuroanatomical structure? • Selective pressure on brain structure associatedwith information process • Ex. bats, primates, birds • Hippocampus - memory, spatial information processing • Lesion experiment • Ex. Black-capped chickadee • Ex. Chickadees and titmouse - hippocampal-lesioned birds… … showed no memory for storage sites

23. □non-food-storers ■ food-storers • Ex. Marsh tit - HP development… … correlates with the act of retrieving stored • Food-storing is associated with enlarged hippocampus. • Limited total brain volume.

24. Sexual differences in spatial memory and hippocampal size • Ex. Vole - sexual dimorphism in polygynous voles in… … home-range size … hippocampal size • Temporal hippocampus enlargement - seasonal neurogenesis • Ex. meadow vole, canary

25. A dedicated cognitive process? • Enhanced spatial memory should exhibit only in food catching. • Ex. food-storers vs. non-storers - storing + retrieving - memorizing (non-storing) • In both tasks, food-storers were more efficient. SORRY~ UNLIKELY !

26. Superior spatial memory for food-storers? 1. Learn spatial tasks faster 2. Memorize more spatial information 3. Support longer retention intervals • Comparison of storers with non-storers - Clark’s nutcrackers’ memory last for months • “window shopping” experiment - Food-storers always outperformed, but with very small differences. O X

27. The Quality and quantity of spatial memory • Lateralization of long-term memory- ex. Marshtit- left eye : spatial information- right eye : non-spatial information

28. 3.5 Social Learning • The use of public information about area, object and behaviour (1) Area copying (2) Object copying (3) Behaviour copying

29. (1) Area copying • An individual directs its behaviour towards the place where others are currently active. • Advantages - Avoid dangerous places - Increase foraging gain • Information-sharing group • Producer-scrounger (PS) game • - the payoff declines with the frequency of use • - PS game leads to better foraging gain than information-sharing group does.

30. (2) Object copying • An individual directs its behaviour towards an object that matches the type attended by others. • Predator and enemy recognition, mate copying, food choice … • Ex. Food choice on Norway rats - rats eat copious amounts of food as members do, even the food is unfamiliar or aversive.

31. HOW? – Adaptive hypotheses ? • Group living promotes social learning- non social animals?? • Ex. Social vs. non-social pigeons - pigeons learn faster when the “tutors” are their own species - same differences for non-social tasks… • - Social/non-social learning not under selection??

32. (3) Behaviour copying • Acquisition of a NOVEL behaviour by seeing another individual use it. • Vocal learning - songbirds • Visual imitation • WHY? – Adaptive hypotheses 1. Non-social learning is hazardous 2. Large environmental changes are predictable 3. Social learning is more accurate

33. 3.6 Cultural Transmission • An extend of social learning • Spread following logistic progression (a) avian bottle opening in the whole of the UK between 1921 and 1947

34. Cumulative spread of foraging innovation over time Japanese macaques (b) washing potatoes(c) washing wheat (d) eating beached fish

35. Japanese macaques (e) unwrapping and eating caramels, (f) eating mangoes(g) eating lemons.

36. Spread speed affecting factors 1. Demonstrator and observer densities - learning rate in proportion to demonstrator density - depressing effect of uninformative bystanders 2. Scrounging - the potential of feeding on food discovered by demonstrators. • Duplicate cage procedure • Pigeons, monkeys, jackdaws, zebra finches

37. Tradition longevity affecting factors • Only behaviour copying gives rise to tradition- yet it’s not enough to sustain tradition • Chain procedure - a previous observer becomes demonstrator for the next observer. • Ex. Food selection tradition in Norway rats - Construct founder groups with certain flavour preference. Replace founders gradually until there was no founder left in the group.

38. Founders’ preference can sustain after they left the group. • The fidelity to the tradition was sensitive to the extend to which rats had access to alternative flavour (non-social learning).

39. 3.7 Future Directions • The change of memory parameter according to environment • Quality and the type of information used • More detail about neuroanatomical structures

40. The End Thank you for your attention!

41. Lateralization of long-term spatial memory- left eye : storing spatial message- right eye : non-spatial message

42. New Nerve Cells Expand Hippocampus Volume in Chickadee • Every autumn, chickadees gather seeds and store them in hundreds of hiding places in trees and on the ground. Over the winter that follows, chickadees faithfully re-visit their caches to feed. • In the fall, as the chickadee is gathering and storing seeds, its hippocampus, texpands in volume by approximately 30% by adding new nerve cells. In the spring, hippocampus shrinks back to its normal size. • Songbirds are the first vertebrates in which brain growth during adulthood has been found to occur. • Black-capped Chickadeethe role played by the hormone estrogen in the growth of the hippocampus. the area of the songbird brain

43. 知識問題| 請問”樫”怎麼唸? • 發問者： YUS ( 初學者 4 級) 發問時間： 2007-02-24 16:18:00 解決時間： 2007-02-24 21:16:26 解答贈點： 5 ( 共有 0 人贊助) 回答： 5 評論： 0 意見： 0網友正面評價 100%( 共有 7 人評價) [ 檢舉] • Q1. 請問"樫"怎麼唸?(請用注音拼出來)Q2. 如何用注音打出來?(因為我是用倉頡打的) • 2007-02-24 16:23:15 補充 To 001 回答者, 我也認為是唸 ㄐㄧㄢ 可是用注音拼的時候就是找不到這個字. • 2007-02-24 16:29:47 補充 倉頡打法為 木 尸 水 土 • 最佳解答 • 發問者自選 • 回答者： [[,,ＲainＢow★〞 ( 初學者 4 級 ) 回答時間： 2007-02-24 16:21:02 [ 檢舉] • 「樫」這個字原本是日本特有的「和製漢字」啦！所以基本上是沒有注音可以唸的，「樫」這個字的日文發音是「かし」（Ka-Shi／ㄎㄚ˙ㄒㄧ），意思是指「橡樹、槲（ㄏㄨˊ）樹」，這種樹木都是材質很堅硬的，故日本才會造「樫」這個字喔！其實用注音輸入法是打不出來的，所以必須藉由倉頡或嘸蝦米輸入法才能鍵出此字，不過基本上「樫」這個字是可以唸成「ㄐㄧㄢ」，因為我查過 Unicode （萬國碼）的官方網站，查到此字的漢語拼音是「 JIAN1 」，換成注音即是唸成「ㄐㄧㄢ」沒錯，就連韓文也是唸成類似「ㄐㄧㄢ」的音（KYEN）喔！總之，唸「ㄐㄧㄢ」沒錯啦！ • 參考資料 http://tw.knowledge.yahoo.com/question/?qid=1205080115670