Biology subjects

Woodruff, G. C.

Publications and source records attributed to Woodruff, G. C..

3 recordsLinked to original sources

bioRxiv2018

A large close relative of C. elegans is slow-developing but not long-lived

BackgroundVariation in body size is thought to be a major driver of a wide variety of ecological and evolutionary patterns, including changes in development, reproduction, and longevity. Caenorhabditis inopinata is a recently-discovered fig-associated nematode that is unusually large relative to other members of the genus, including the closely related model system C. elegans. Here we test whether the dramatic increase in body size has led to correlated changes in key life history and developmental parameters within this species.\n\nResultsUsing four developmental milestones, C. inopinata was found to have a slower rate of development than C. elegans across a range of temperatures. Despite this, C. inopinata did not reveal any differences in adult lifespan from C. elegans after accounting for differences in developmental timing and reproductive mode. C. inopinata fecundity was generally lower than that of C. elegans, but fitness improved under continuous-mating, consistent with sperm-limitation under gonochoristic (male/female) reproduction. C. inopinata also revealed greater fecundity and viability at higher temperatures.\n\nConclusionConsistent with observations in other ectotherms, slower growth in C. inopinata indicates a potential trade-off between body size and developmental timing, whereas its unchanged lifespan suggests that longevity is largely uncoupled from its increase in body size. Additionally, temperature-dependent patterns of fitness in C. inopinata are consistent with its geographic origins in subtropical Okinawa. Overall, these results underscore the extent to which changes in ecological context and body size can shape life history traits.

evolutionary biology↗

bioRxiv2018

Two levels of host-specificity in a fig-associated Caenorhabditis

BackgroundBiotic interactions are ubiquitous and require information from ecology, evolutionary biology, and functional genetics in order to be completely understood. However, study systems that are amenable to investigations across such disparate fields are rare. Figs and fig wasps are a classic system for ecology and evolutionary biology with poor functional genetics; C. elegans is a classic system for functional genetics with poor ecology. In order to help bridge these disciplines, here we describe the natural history of a close relative of C. elegans, C. sp. 34, that is associated with the fig Ficus septica and its pollinating Ceratosolen wasps.\n\nResultsTo understand the natural context of fig-associated Caenorhabditis, fresh F. septica figs from four Okinawan islands were sampled, dissected, and observed under microscopy. C. sp. 34 was found in all islands where F. septica figs were found. C. sp. 34 was routinely found in the fig interior and almost never observed on the outside surface. Caenorhabditis was only found in pollinated figs, and C. sp. 34 was more likely to be observed in figs with more foundress pollinating wasps. Actively reproducing C. sp. 34 dominated younger figs, whereas older figs with emerging wasp progeny harbored C. sp. 34 dispersal larvae. Additionally, C. sp. 34 was observed dismounting from plated Ceratosolen pollinating wasps. C. sp. 34 was never found on non-pollinating, parasitic Philotrypesis wasps. Finally, C. sp. 34 was only observed in F. septica figs among five Okinawan Ficus species sampled.\n\nConclusionThese observations suggest a natural history where C. sp. 34 proliferates in young F. septica figs and disperses from old figs on Ceratosolen pollinating fig wasps. The fig and wasp host specificity of this Caenorhabditis is highly divergent from its close relatives and frames hypotheses for future investigations. This natural co-occurrence of the fig/fig wasp and Caenorhabditis study systems sets the stage for an integrated research program that can help to explain the evolution of interspecific interactions.

ecology↗

bioRxiv2017

Dramatic evolution of body length due to post-embryonic changes in cell size in a newly discovered close relative of C. elegans

Understanding morphological diversity--and morphological constrainto--has been a central question in evolutionary biology since its inception. Nematodes of the genus Caenorhabditis, which contains the well-studied model system C. elegans, display remarkable morphological consistency in the face of extensive genetic divergence. Here, we provide a description of the broad developmental patterns of a recently discovered species, C. sp. 34, which was isolated from fresh figs in Okinawa and which is among the closest known relatives of C. elegans. C. sp. 34 displays an extremely large body size and can grow to be nearly twice as long as C. elegans and all other known members of the genus. Observations of the timing of developmental milestones reveal that C. sp. 34 develops about twice as slowly as C. elegans. Measurements of embryo and larval size show that the size difference between C. sp. 34 and C. elegans is largely due to post-embryonic events, particularly during the transition from larval to adult stages. This difference in size is not attributable to differences in germ line chromosome number or the number of somatic cells. The overall difference in body size is therefore largely attributable to changes in cell size via increased cytoplasmic volume. Because of its close relationship to C. elegans, the distinctness of C. sp. 34 provides an ideal system for the detailed analysis of evolutionary diversification. The context of over forty years of C. elegans developmental genetics also reveals clues into how natural selection and developmental constraint act jointly to promote patterns of morphological stasis and divergence in this group.

evolutionary biology↗