ANB 218A Fall 2013 Movement and Migration Part 2

Outline 1.Introduction – kinds of movement evolutionary theory and migration 2.Concept of annual routines (life cycles) and phenotypic flexibility 3.Life history stages and how environmental conditions influence their progression 4. Classification of environmental cues: predictable, unpredictable 5. Genetic basis for migratory traits 6. Conclusions

Outline 1.Introduction – kinds of movement evolutionary theory and migration 2.Concept of annual routines (life cycles) and phenotypic flexibility 3.Life history stages and how environmental conditions influence their progression 4. Classification of environmental cues: predictable, unpredictable 5. Genetic basis for migratory traits 6. Conclusions

Environmental information can be divided into two categories Predictable cues (reliable, temporally relevant): Initial predictive – daylength, circannual rhythms, seasonality Local predictive –Current environmental conditions, temperature, food, other resources, wet / dry seasons, geomagnetic information, planetary cues, etc Unpredictable cues (labile, unexpected): - - Huge swings in climatic conditions, food supply, social dominance, disease, predators - Exposure leads to a modification of the current LH stage

Classification of environmental cues Storm fronts/prevailing winds Seasonal Temperature Ocean currents Landscapes Celestial cues Setting sun Polarized light Geomagnetic forces Predators Seasonal fluxes of food Solar time cycle Storms Pollution Disease Loss of habitat Change in food Global changes Social conditions Predictable CuesUnpredictable Cues

Early phase Late phase

Effect of the magnetic field on orientation of European robins, Erithacus rebecula

Autumn recoveries of Thrush Nightingale from SE Scandinavia to E Mediterranean. (Kullberg et al. 2003) Early Migration Later Migration Experimentals Controls

Long distance migrations of marine turtles raise questions of the source of cues

Ascension Islands

Magnetic lineations along the seafloor created by fracture zones along spreading ridges

Classification of environmental cues Storm fronts/prevailing winds Seasonal Temperature Ocean currents Landscapes Celestial cues Setting sun Polarized light Geomagnetic forces Predators Seasonal fluxes of food Solar time cycle Storms Pollution Disease Loss of habitat Change in food Global changes Social conditions Predictable CuesUnpredictable Cues

Facultative responses to an unpredictable cue – Emergency life history stage (Wingfield et al 1998)

Emergency life history stage represents interrelationships of substages (Wingfield and Ramenofsky, 2011)

Modeling responses to unpredictable events or labile perturbation factors: Allostatic Load. 2

Energy metabolism Immune function Behavior b-ENDORPHIN Analgesia, behavioral effects

(Landys, Ramenofsky, Wingfield, 2006) Associations of homeostasis, allostasis and physiological state

Meta Landys working with Bar-tailed godwits in the Netherlands Taking an Allostatic Load Approach to the studies of migration

Departure biology of long Bar-tailed Godwits from Spring stop-over site (Landys et al. 2002)

Corticosterone ng/ml

Do these peaks of corticosterone represent allostatic overload? One might ask:

NO!

Model of the relationships across available energy (resources), demand and glucocortiocoid levels (Landys et al 2006)

Classification of environmental cues Storm fronts/prevailing winds Seasonal Temperature Ocean currents Landscapes Celestial cues Setting sun Polarized light Geomagnetic forces Predators Seasonal fluxes of food Solar time cycle Storms Pollution Disease Loss of habitat Change in food Global changes Social conditions Predictable CuesUnpredictable Cues

Jenni et al, 2000 Corticosterone levels of a variety of transequatorial migrants following migration across the Mediterranean Sea during spring migration.

Behavioral responses to the unpredictable - Facultative movements - Partial migrants Within a wintering flock some members will remain on or nearby the breeding grounds while others will migrate away depending upon local environmental conditions. This is also considered an evolutionary stable strategy (ESS). Schwabl et al 1985

Map of Europe Breeding range of European Blackbird Wintering range Adults remain On breeding range

SEVEREMILD Adult First year Male European Blackbird Weather conditions Corticosterone, ng/ml SEVEREMILD Adult First year Female European Blackbird Weather conditions Corticosterone, ng/ml (Schwabl et al., 1985)

Geographical range of European Blackbird, Turdus merula Residents Partial migrants (Partecke et al., 2007)

Red crossbill: a facultative migrant Irregular movements of flocks that coincide with availability of cone crops Red Crossbill (Loxia curviostra) Douglas fir cone Pseudotsuga Menziesii

(Hahn et al., 2008) Annual reproductive schedules of red crossbills

Suggestions of how Red crossbills react to food shortages (Cornelius et al., Proc. R. Soc., 2010)

Public information and movement in red crossbills (Cornelius et al., Proc. R. Soc., 2010)

Key Points 1.Migrants respond to both predictable and unpredictable environmental cues but the physiological mechanisms differ 2.Predictable cues influence the speed of progression through the life history stage whereas, unpredictable cues induce an alternative - Emergency life history stage The physiological mechanisms of this have been aligned with the Allostatic load models

Outline 1.Introduction – kinds of movement evolutionary theory and migration 2.Concept of annual routines (life cycles) and phenotypic flexibility 3.Life history stages and how environmental conditions influence their progression 4. Classification of environmental cues: predictable, unpredictable 5. Genetic basis for migratory traits 6. Conclusions

Be (Berthold and Pulido, 1994)

Morphological changes in phenotype with range expansion of a long-distance migrant: Assortative mating promotes microevolution of a migratory population (Gunnarsson et al 2012)