Biology subjects

Blanchette, A.

Publications and source records attributed to Blanchette, A..

3 recordsLinked to original sources

bioRxiv2026

Genetic diversity of endangered Acropora spp. corals in Bonaire: implications for restoration and gene banking

Species restoration is a valuable tool to combat biodiversity loss. However, maintaining genetic diversity in species restoration is challenging, particularly for species that can reproduce asexually, such as plants and corals, because a seemingly diverse collection of individuals could be composed of many clones of a few genotypes. Caribbean elkhorn and staghorn corals (Acropora palmata, A. cervicornis) are critically endangered reef-building corals that are a major target for restoration. To better understand the genetic diversity of an Acropora spp. restoration program and interpret local population genetic structure, we conducted microsatellite genotyping on the gene banks of 35 A. palmata lineages and 25 A. cervicornis lineages maintained by Reef Renewal Foundation Bonaire (RRFB) in the Caribbean Netherlands. We found that RRFB had high genotypic richness for A. palmata (0.971) and A. cervicornis (1.0) and estimated that they captured 88.9% and 74.7% of Bonaires microsatellite asymptotic allelic diversity, respectively. Compared to populations of Acropora spp. studied in other locations across the Caribbean, A. palmata in Bonaire had relatively low expected heterozygosity, while A. cervicornis was greater than approximately half of other populations. Across Bonaire and for both coral species, we did not find evidence for genetic structuring among spatially separated subpopulations, indicating that both species are likely well-connected around the island. Together, these results demonstrate the effectiveness of RRFBs strategies to capture high genetic diversity and can be used to inform future initiatives on coral sexual breeding and assisted gene flow beyond Bonaire.

genetics↗

bioRxiv2024

Extreme lead tolerance in an urban lizard

Lead (Pb) is an extremely toxic heavy metal pollutant pervasive in many environments with serious health consequences for humans and wildlife. We found that Cuban brown anole lizards (Anolis sagrei) in New Orleans, USA, have the highest mean (955{+/-}877 {micro}g/dL; N = 40) and individual (3,192 {micro}g/dL) blood lead levels of any free-living vertebrate reported to date. Unexpectedly, this extreme field lead exposure did not decrease performance in whole-organism traits commonly affected by lead (balance, sprint speed, endurance). To identify toxicity thresholds, we employed a 60-day lead-dosing experiment and found that the brown anole blood lead threshold for decreased whole-organism performance is over an order of magnitude higher than the already extreme mean field concentration (10,600 {micro}g/dL). Transcriptomic analysis of brain and liver from lizards in high and low lead sites revealed minor effects of lead exposure. However, several of the differentially expressed genes function in metal ion homeostasis and oxygen carrying capacity, pointing to cellular mechanisms that may contribute to high lead tolerance in these animals. The brown anole may be the most lead-tolerant vertebrate known to date and has the potential to serve as a powerful model system to help us understand mechanisms of lead tolerance.

ecology↗

bioRxiv2021

The evolution of size-dependent competitive interactions promotes species coexistence

O_LITheory indicates that competing species coexist in a community when intraspecific competition is stronger than interspecific competition. When body size determines the outcome of competitive interactions between individuals, coexistence depends also on how resource use and the ability to compete for these resources change with body size. Testing coexistence theory in size-structured communities, therefore, requires disentangling the effects of size-dependent competitive abilities and niche shifts. C_LIO_LIHere, we tested the hypothesis that the evolution of species and size-dependent competitive asymmetries increased the likelihood of coexistence between interacting species. C_LIO_LIWe experimentally estimated the effects of size-dependent competitive interactions on somatic growth rates of two interacting fish species, Trinidadian guppies (Poecilia reticulata) and killifish (Rivulus hartii). We controlled for the effects of size-dependent changes in the niche at two competitive settings representing the early (allopatric) and late (sympatric) evolutionary stages of a killifish-guppy community. We fitted the growth data to a model that incorporates species and size-dependent competitive asymmetries to test whether changes in the competitive interactions across stages increased the likelihood of species coexistence from allopatry to sympatry. C_LIO_LIWe found that guppies are competitively superior to killifish but were less so in sympatric populations. The decrease in the effects of interspecific competition on the fitness of killifish and increase in the interspecific effect on guppies fitness increased the likelihood that sympatric guppies and killifish will coexist. However, while the competitive asymmetries between the species changed consistently between allopatry and sympatry between drainages, the size-dependent competitive asymmetries varied between drainages. C_LIO_LIThese results demonstrate the importance of integrating evolution and trait-based interactions into the research of how species coexistence. C_LI

ecology↗