preferences similar to those of green turtles undergo CG in the wild (Bjorndal et al. 2003),

although the mechanism for this growth pattern is unknown.

 The purpose of the first phase of my research was to manipulate food availability in

juvenile green turtles under controlled conditions to test whether previously food-restricted

turtles can undergo CG and to evaluate hyperphagia and enhanced food conversion efficiency as

possible mechanisms for this growth pattern. The results of Chapter 2 indicated that previously

food-restricted green turtle juveniles are indeed capable of transient growth compensation after a

return to ad libitum feeding. This finding suggests that growth rates of turtles under conditions of

continuously high food availability are optimal rather than maximal (Metcalfe and Monaghan

2001) and that trade-offs between growth and fitness probably exist.

 Rapid growth in many species may be associated with a variety of costs, many of which

may not be paid until late in life (Einum and Fleming 2000 and references therein, Metcalfe and

Monaghan 2001, Altmann and Alberts 2005, Nagy and Holmes 2005). To pursue this hypothesis,

I examined antioxidant function of tissues from green turtles that had undergone CG.

Antioxidants prevent free-radical induced oxidative damage to nucleic acids and proteins by

converting reactive oxygen species (ROS) into less noxious compounds (Ji and Leichtweis 1997,

Gredilla and Barja 2005). Caloric restriction depresses the rate of production of ROS

(L6pez-Torres et al. 2002, Barj a 2004) and attenuates the accrual of irreparable damage to

cellular macromolecules (Hyun et al. 2006). As a result, dietary restriction slows aging and thus

extends lifespan relative to continuous ad libitum feeding in a diversity of species (Weindruch

and Walford 1988, Austad 1989, Mair et al. 2003, Vaupel et al. 2003, Hatle et al. 2006b).

Because ad libitum feeding is typically accompanied by accelerated aging, it is possible that

periods of rapid growth induced by high food availability after a period of nutritional stress may