PhotoperiodPhodopusLightPeriodicitySeasonsMelatoninArvicolinaeReproductionSexual MaturationTestisPineal GlandPeromyscusFlowersCircadian RhythmProlactinOrgan SizeSeminal VesiclesLuteinizing HormoneDarknessSheepLightingTestosteroneMesocricetusEnvironment, ControlledCricetinaeEstrusFlorigenGene Expression Regulation, PlantBody WeightPhysiological ProcessesAcclimatizationTorporSexual Behavior, AnimalStarlingsFollicle Stimulating HormoneMarsupialiaAnestrusGonadsActivity CyclesSparrowsMoltingGenes, PlantPortulacaceaeTemperatureArabidopsisGenitalia, MaleRodentiaBiological ClocksAntlersPlant LeavesHypothalamusArabidopsis ProteinsHoof and ClawOdonataTime FactorsOvaryTriturusPlant ProteinsSpermatogenesisSuprachiasmatic NucleusPituitary GlandProgesteroneOvariectomyPlant StemsPregnancyCastrationGibberellinsPhytochrome AFood DeprivationCold TemperatureCheirogaleidaeDrug ImplantsLactationOrchiectomyEstradiolCryptochromesPhytochromeMacropodidaeHibernationCarnivoraPhytochrome BAdaptation, PhysiologicalGoats