Because of the complications in achieving the necessary long-term observations and experiments, the nature and adaptive value of seasonal time-keeping mechanisms in long-lived organisms remain understudied. Here we present the results of a 20-year-long study of the repeated seasonal changes in body mass, plumage state, and primary molt of 45 captive red knots Calidris canutus islandica, a High Arctic breeding shorebird that spends the nonbreeding season in temperate coastal areas. Birds kept outdoors and experiencing the natural photoperiod of the nonbreeding area maintained sequences of life-cycle stages, roughly following the timing in nature. For 6 to 8 years, 14 of these birds were exposed to unvarying ambient temperature (12 °C) and ph...
We present experimental evidence for endogenous control of circannual rhythms in a long-distance mig...
1. Seasonal carry-over effects may be important structuring components of avian life-history cycles....
Phenotypic flexibility in shorebirds has been studied mainly in the context of adjustments to migrat...
Because of the complications in achieving the necessary long-term observations and experiments, the ...
Because of the complications in achieving the necessary long-termobservations and experiments, the n...
Knots Calidris canutus live highly seasonal lives, breeding solitarily on high arctic tundra and spe...
The failure of animals to fit all life-cycle stages into an annual cycle could reduce the chances of...
Knots Calidris canutus live highly seasonal lives, breeding solitarily on high arctic tundra and spe...
The failure of animals to fit all life-cycle stages into an annual cycle could reduce the chances of...
The failure of animals to fit all life-cycle stages into an annual cycle could reduce the chances of...
During the last three of 20 years kept as a pet, a red knot (Calidris canutus) went through two comp...
Four Great Knots (Calidris tenuirostris) were kept for six years in a constant-temperature indoor av...
Four Great Knots (Calidris tenuirostris) were kept for six years in a constant-temperature indoor av...
We present experimental evidence for endogenous control of circannual rhythms in a long-distance mig...
We present experimental evidence for endogenous control of circannual rhythms in a long-distance mig...
1. Seasonal carry-over effects may be important structuring components of avian life-history cycles....
Phenotypic flexibility in shorebirds has been studied mainly in the context of adjustments to migrat...
Because of the complications in achieving the necessary long-term observations and experiments, the ...
Because of the complications in achieving the necessary long-termobservations and experiments, the n...
Knots Calidris canutus live highly seasonal lives, breeding solitarily on high arctic tundra and spe...
The failure of animals to fit all life-cycle stages into an annual cycle could reduce the chances of...
Knots Calidris canutus live highly seasonal lives, breeding solitarily on high arctic tundra and spe...
The failure of animals to fit all life-cycle stages into an annual cycle could reduce the chances of...
The failure of animals to fit all life-cycle stages into an annual cycle could reduce the chances of...
During the last three of 20 years kept as a pet, a red knot (Calidris canutus) went through two comp...
Four Great Knots (Calidris tenuirostris) were kept for six years in a constant-temperature indoor av...
Four Great Knots (Calidris tenuirostris) were kept for six years in a constant-temperature indoor av...
We present experimental evidence for endogenous control of circannual rhythms in a long-distance mig...
We present experimental evidence for endogenous control of circannual rhythms in a long-distance mig...
1. Seasonal carry-over effects may be important structuring components of avian life-history cycles....
Phenotypic flexibility in shorebirds has been studied mainly in the context of adjustments to migrat...