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Recognition Systems: 1. What are they (types of recognition)? 2. How do they work? 3. Optimal Threshold Models

The Major Transitions Maynard Smith & Szathmáry Replicating molecules --->Molecules in protocells 2. Independent replicators ---> Chromosomes 3. RNA as gene and enzyme ---> DNA genes, protein enzymes 4. Bacteria (prokaryotes) ---> Eukaryotes (organelles) 5. Asexual clones ---> Sexual populations 6. Single-celled organisms ---> Multicellularity 7. Solitary individuals ---> Eusocial colonies 8. Primate societies ---> Human societies (language)

The Major Transitions Maynard Smith & Szathmáry Replicating molecules --->Molecules in protocells 2. Independent replicators ---> Chromosomes 3. RNA as gene and enzyme ---> DNA genes, protein enzymes 4. Bacteria (prokaryotes) ---> Eukaryotes (organelles) 5. Asexual clones ---> Sexual populations 6. Single-celled organisms ---> Multicellularity 7. Solitary individuals ---> Eusocial colonies 8. Primate societies ---> Human societies (language)

Recognition Systems Self / Non self Kin Recognition Mate Individual Species Prey/Predators

Recognition Systems Self / Non self Kin Recognition Mate Individual Species Prey/Predators Recognition vs. Discrimination

Recognition Systems Allorecognition systems Self / Non self auto immune systems (MHC) self incompatibility (plants) sex determining locus (hymenoptera) Genetic basis, highly variable (many alleles - most alleles known for almost any gene).

Recognition Systems Intraspecific recognition Kin Recognition formation of social groups cooperation / altruism mating behavior Distinguish others based upon their degree of genetic relatedness. Can be learned or innate. Self-referent or phenotype matching.

Recognition Systems Intraspecific recognition Kin Recognition formation of social groups cooperation / altruism mating behavior

Recognition Systems Intraspecific recognition Mate Recognition finding mates (right species) mate choice (right individual) Individual Recognition pair bonds neighbors/territoriality Species Recognitionconspecific attraction territoriality mate choice

“The grossest blunder in sexual preference, which we can conceive of an animal making, would be to mate with a species different from its own […]” Ronald A. Fisher (1958)

Recognition Systems Interspecific recognition Species Recognitionpredator avoidance prey capture (foraging) host / parasite association naïve prey responding to cues of introduced predators learned responseinnate response New Zealand Robin and mustellids Maloney & McLean 1995 Rana aurora bullfrogs and crayfish Pearl et al. 2003

Conspecific Recognition and Social Development in Brown-headed Cowbirds (Molothrus ater)

“[…] Brown-headed Cowbird behaviour is strongly influenced by learning, just as in other species. The Cowbird’s trick is to delay learning until it has become independent and has followed a genetic predisposition to seek company with its own kind. This means that […] it avoids the problems encountered by Lorenz’s geese and the cross- fostered Zebra Finches Davies (2000) “Brood parasites seem to know just who they are at an early age. Brown-headed Cowbirds join flocks of their own kind after they gain independence from their foster parents. This species recognition is most likely under genetic control and is a necessary precondition of brood parasitism.” Ortega (1998) Conspecific recognition in parasitic cowbirds

Recognition Systems Other types of recognition Abiotic conditionshabitat choice nest site selection precipitation / temperature

Recognition Systems Other types of recognition Abiotic conditionshabitat choice nest site selection precipitation / temperature Lesser Prairie-Chicken

Components of recognition systems: Evaluator (receiver, discriminator, actor): Individual whose behavior is modified by a signal. Signaler (target, cue-bearer, recipient): Individual creating a signal to illicit a response. (usually different individuals except in self recognition)

Components of recognition systems: Label - a signal, cue, or stimulus that is perceived by the evaluator. ( can include chemical odors, cell surface proteins, songs, color patterns, stereotypic displays) Template - what the evaluator uses to compare the signal. (can be genetically “hard wired” or acquired during development through learning or imprinting) Referent - basis for a template when not genetically based

Components of recognition systems: Decision rules - Different types of recognition systems may employ different matching rules. Exact match for acceptance - foreign label rejection Partial match is sufficient - shared label acceptance Behavior can very depending on degree of match. evaluator templatesignal signaler

Components of recognition systems: 1.Production - the nature and development of labels (cues) in signalers. 2.Perception - the sensory detection of labels by evaluators followed by a comparison of labels to a template. (includes the ontogeny of templates) 3.Action - modification of behavior in response to an assessment of the signaler’s label relative to the evaluator’s template.

Nest mate recognition in social insects Label Template A E AE

Label Template ABCD EF AE A B A B Nest mate recognition in social insects Diet (C) Nest material (D) Signal = cuticular hydrocarbons: acquired from genes, diet and nest

Label Template ABCD EF AE A B A B Nest mate recognition in social insects Diet (C) Nest material (D) Signal = cuticular hydrocarbons: acquired from genes, diet and nest Referent

Foreign label rejection Label Template ABCD AB CB A B C D “reject”“accept”

Correlation of hydrocarbon profiles between nests Average aggression score

Optimal Threshold Model adapted from Reeve 1989, Starks 2003

Optimal Threshold Model adapted from Reeve 1989, Starks 2003 signals you want to accept signals you want to reject acceptance errors rejection errors

Dissimilarity between template and cues Frequency Ideally, there would be no overlap between signals you want to accept or reject.

Dissimilarity between template and cues Frequency However, the distribution and variation of signals (cues) can be constrained by selection or the environment.

Dissimilarity between template and cues Frequency Moreover, the threshold of response may also be constrained by ability to distinguish among signals, or can evolve rapidly in response to selection.

Dissimilarity between template and cues Frequency Moreover, the threshold of response may also be constrained by ability to distinguish among signals, or can evolve rapidly in response to selection. Threshold shifts to the left (more stringent) to reduce acceptance errors if they are too costly.

Dissimilarity between template and cues Frequency Moreover, the threshold of response may also be constrained by ability to distinguish among signals, or can evolve rapidly in response to selection. Threshold shifts to the right (less stringent) to reduce rejection errors if they are too costly.

Frequency

Dissimilarity score 01

Mate Kin Possible overlap of recognition cues/perceptual filters: Species Individual Species Mate Kin Individual Recognition: Production Perception Action cue brainresponse

Mate Kin Possible overlap of recognition cues/perceptual filters: Species Individual Species Mate Kin Individual Recognition: Production Perception Action cue brainresponse