Related by context. Frequent words. (Click for all words.) 60 vocalisations 56 vocalizations 56 zebra finches 55 sexual dimorphism 54 evolutionary origins 54 morphologically 54 sensory organs 53 photoperiod 52 organismal 52 female reproductive tract 52 sensory stimuli 52 taste receptors 52 odorant receptors 52 sex hormone estrogen 52 olfactory receptors 52 spotted hyenas 52 MHC genes 52 brain lesions 52 neuroimaging studies 52 odorants 52 papillae 52 developmental abnormalities 52 olfactory bulb 52 vaginal secretions 51 reproductive hormones 51 motile 51 olfaction 51 neural crest cells 51 herbivory 51 visual stimuli 51 neural mechanisms 51 reproductively 51 circadian clocks 51 auditory cortex 51 ganglion cells 51 nonhuman primates 51 methylation patterns 51 pheromones 51 spatio temporal 51 gene expression patterns 51 researchers hypothesize 51 melanopsin 51 physiologically relevant 51 morphological 51 hematopoietic cells 50 neural circuitry 50 histone modifications 50 gut microbiota 50 quantitative measurements 50 plasmon 50 corticosterone 50 chemical reactivity 50 reproduce asexually 50 apoE 50 vocalization 50 nonhuman primate 50 neuropeptides 50 somatosensory 50 synchrony 50 spermatogenesis 50 ultracold atoms 50 echidnas 50 experimentally induced 50 FGF# 50 Sertoli cells 49 physiological 49 sensory inputs 49 biophysical 49 zebra finch 49 physiological parameters 49 otoliths 49 retinal ganglion cells 49 neural circuits 49 rhesus monkeys 49 sociality 49 differentially expressed genes 49 placental mammals 49 physiologic 49 habituation 49 gut microbes 49 neonate 49 afferent 49 stimuli 49 Pheromones 49 Xenopus 49 mutagens 49 evolutionarily conserved 49 electrophysiological 49 Chlamydomonas 49 estrus 48 external stimuli 48 biologically relevant 48 physiological responses 48 gonadal 48 adipocyte 48 echolocation 48 toothed whales 48 sensory neurons 48 luteolin 48 relatedness 48 rhesus macaques