Does energy availability predict gastropod reproductive strategies?

Abstract

The diversity of reproductive strategies in nature is shaped by a plethora of factors including energy availability. For example, both low temperatures and limited food availability could increase larval exposure to predation by slowing development, selecting against pelagic and/or feeding larvae. The frequency of hermaphroditism could increase under low food availability as population density (and hence mate availability) decreases. We examine the relationship between reproductive/life-history traits and energy availability for 189 marine gastropod families. Only larval type was related to energy availability with the odds of having planktotrophic larvae versus direct development decreasing by 1% with every one-unit increase in the square root of carbon flux. Simultaneous hermaphroditism also potentially increases with carbon flux, but this effect disappears when accounting for evolutionary relationships among taxa. Our findings are in contrast to some theory and empirical work demonstrating that hermaphroditism should increase and planktotrophic development should decrease with decreasing productivity. Instead, they suggest that some reproductive strategies are too energetically expensive at low food availabilities, or arise only when energy is available, and others serve to capitalize on opportunities for aggregation or increased energy availability.

Energetic increases lead to niche packing in deep-sea wood falls

“…Certain traits show increased abundance on larger wood falls (figure 2). This could occur because increases in energy allow for greater coexistence of species with certain functional traits [24,[30][31][32]. For example, increased energy allows for greater dominance of more mobile fauna.…”

Transects in the deep: Opportunities with tele-operated resident seafloor robots

“…Reproductive strategies and phenology in many deep-sea animals are still largely unknown (Danovaro et al, 2014;Danovaro et al, 2020). In gastropods in particular, food availability may trigger specific strategies or aggregations which are otherwise inhibited as too expensive from an energetic point of view (McClain et al, 2014). In April 2014, a dense aggregation of buccinid gastropods was encountered on the western flank of the gas hydrate mound monitored by the crawler (Figure 2A).…”

On some hypotheses of diversity of animal life at great depths on the sea floor

“…Likewise, the energetic limits of the deep oceans may exclude or greatly constrain some species with high metabolic demands, such as nudibranchs (McCain et al . ) and sharks (Priede et al . ).…”

“…Rex (1973) argued that one of the factors that may cause the observed decline in diversity at depth was that the low energy availability of the abyssal plain led to decreased consumer density and did not permit for predator species. Likewise, the energetic limits of the deep oceans may exclude or greatly constrain some species with high metabolic demands, such as nudibranchs (McCain et al 2014) and sharks ). The differences in metabolic demands among taxa (McClain et al 2012a,b,c) may also account for differing PDRs among different groups.…”