News News

Army ant invasion of leatherback nests in Gabon

Egg mortality is one of the main factors affecting life history and conservation of oviparous species. A massive and cryptic colonisation of many leatherback turtle (Dermochelys coriacea) eggs is presented in the most important rookery for the species in Gabon. A total of 163 nests were exhumed at Kingere beach, revealing that only 16.7% of eggs produced hatchlings. In the 59% of the nests, more than half of the eggs were dead and attacked by invertebrates and 94% had at least one egg affected by invertebrates. The rate of eggs and SAGs (yolkless eggs) affected by invertebrates within a clutch ranged from 0% to 100%, with an average proportion of 39% and 52%, respectively. The most common invertebrates interacting with the eggs were ghost crabs and insects that affected 51% and 82% of the nests, respectively. Crab and insect co-occurred in 33% of the affected nests. Ants, identified as Dorylus spininodis (Emery 1901) were found in 56% of the excavated nests. However, it was not possible to determine if the ants predated alive eggs or scavenged dead eggs. Very often, hundreds of ants were found drowned within dead eggs. Termites and other invertebrates were associated with the clutch environment and identified as opportunistic feeders, being this is the first record of interaction between termites and sea turtle eggs. An unusual ecological interaction within the leatherback clutches between termites and ants was found in 11% of the nests. The abrupt transition between the soil forest and the beach might be favouring a thriving microbial and invertebrate activity in the sand profile that colonises the nests. informacion[at]ebd.csic.es: Ikaran et al (2020) Cryptic massive nest colonisation by ants and termites in the world's largest leatherback turtle rookery Ethol Ecol Evol 2020. Doi 10.1080/03949370.2020.1715487


https://www.tandfonline.com/doi/abs/10.1080/03949370.2020.1715487
Average (0 Votes)

Latest News Latest News

Back

Adaptation to high-altitude habitats in the Eastern honey

Adaptation to high-altitude habitats in the Eastern honey

The Eastern honey bee Apis cerana is of central importance for agriculture in Asia. It has adapted to a wide variety of environmental conditions across its native range in southern and eastern Asia, which includes high?altitude regions. Eastern honey bees inhabiting mountains differ morphologically from neighboring lowland populations, and may also exhibit differences in physiology and behavior. The genomes of 60 Eastern honey bees collected from high and low altitudes in Yunnan and Gansu provinces, China, were compared to infer their evolutionary history and to identify candidate genes that may underlie adaptation to high altitude. Using a combination of F_ST?based statistics, long?range haplotype tests, and population branch statistics, several regions of the genome were identified that appear to have been under positive selection. These candidate regions were strongly enriched for coding sequences and had high haplotype homozygosity and increased divergence specifically in highland bee populations, suggesting they have been subjected to recent selection in high altitude habitats. Candidate loci in these genomic regions included genes related to reproduction and feeding behavior in honey bees. Functional investigation of these candidate loci is necessary to fully understand the mechanisms of adaptation to high?altitude habitats in the Eastern honey bee. The results of this research will be very useful to monitor the populations of Asian bees and establish conservation priorities. Pollination services provided by bees are essential for food production throughout the world, but Asian bee populations in China have been declining since the early 20th century due to changes in agricultural practices and the introduction of non-native bees. Therefore, it is important to understand how populations of this species adapt to different environmental conditions such as altitude, as this can help improve conservation efforts and management. informacion[at]ebd.csic.es: Montero-Mendieta et al (2018) The genomic basis of adaptation to high-altitude habitats in the Eastern honey bee (Apis cerana). Mol Ecol DOI 10.1111/mec.14986.


https://www.ncbi.nlm.nih.gov/pubmed/30576015