Parents know best: transgenerational predator recognition through parental effects

Abstract

In highly biodiverse systems, such as coral reefs, prey species are faced with predatory threats from numerous species. Recognition of predators can be innate, or learned, and can help increase the chance of survival. Research suggests that parental exposure to increased predatory threats can affect the development, behaviour, and ultimately, success of their offspring. Breeding pairs of damselfish (Acanthochromis polyacanthus) were subjected to one of three olfactory and visual treatments (predator, herbivore, or control), and their developing embryos were subsequently exposed to five different chemosensory cues. Offspring of parents assigned to the predator treatment exhibited a mean increase in heart rate two times greater than that of offspring from parents in herbivore or control treatments. This increased reaction to a parentally known predator odour suggests that predator-treated parents passed down relevant threat information to their offspring, via parental effects. This is the first time transgenerational recognition of a specific predator has been confirmed in any species. This phenomenon could influence predator-induced mortality rates and enable populations to adaptively respond to fluctuations in predator composition and environmental changes.

Welcome to the Pyrocene: Animal survival in the age of megafire

“…As with predator cues, recognition of fire cues may be innate, driven by natural selection (Atherton & McCormick, 2020), or acquired through learning (Griffin, 2004). The responses of the Audubon Zoo sleepy lizards suggest an innate recognition of compounds in smoke, as many of the individuals lacked ontogenetic experience with fire (Mendyk et al, 2020).…”

A short pre-conception bout of predation risk affects both children and grandchildren

“…Research on TGP in other mammal species found that parental exposure to predation risk can increase pre-weaning mortality and alter the development, behavior, and neurobiology of surviving F1 offspring 21 . In damselfish, parental exposure to cues from one predator species increased embryonic responses to cues from that predator but not to the cues from a novel predator species 46 . Importantly, TGP is not confined to vertebrate taxa 63 : parental exposure to predator cues alters F1 anti-predator behavior in crickets 43 and several snail species 28 , 44 .…”

“…The ecological implications of such changes are profound since it extends the ‘window’ for stress exposure effects well beyond the short period of pregnancy. Increasing the period during which parental stressors can affect future generations may improve the likelihood of producing offspring suited to their environment, a major benefit of TGP 45 , 46 . Preconception maternal exposure to predator cues altered F1 offspring phenotype in several water flea species 47 , 48 and both F1 and F2 offspring in rotifers 49 .…”

“…Few free-living animals, for instance, would survive hours of close-proximity exposure to a predator 52 – 54 . While such changes generally benefit future generations 38 , 46 , 57 , they may also be maladaptive 21 ; understanding when such effects occur and how they manifest themselves is critical to improving our understanding of transgenerational plasticity.…”

Welcome to the Pyrocene: animal survival in the age of megafire

“…As with animal predator cues, recognition of fire cues may be innate, driven by natural selection (Atherton & McCormick, 2020), or acquired through learning (Griffin, 2004). The responses of the Audubon Zoo sleepy lizards suggest an innate recognition of compounds in smoke, as many of the individuals lacked ontogenetic experience with fire (Mendyk et al, 2020).…”