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Full-Text Articles in Life Sciences

A Threat To New Zealand's Tuatara Heats Up, Kristine L. Grayson, Nicola J. Mitchell, Nicola J. Nelson Sep 2014

A Threat To New Zealand's Tuatara Heats Up, Kristine L. Grayson, Nicola J. Mitchell, Nicola J. Nelson

Biology Faculty Publications

No matter how many times we head to one of New Zealand's offshore islands, the feelings are always a mix of sheer awe at the beauty and biodiversity preserved in these special refuges and lingering nerves. Did we remember all the gear? Do we have enough food and water in case we get stuck? Can the helicopter land on the side of a cliff in these winds? These epic journeys are in pursuit of a lone remnant of the reptile evolutionary tree, with a unique ecology that has big implications under climate change.


Sex Ratio Bias And Extinction Risk In An Isolated Population Of Tuatara (Sphenodon Punctatus), Kristine L. Grayson, Nicola J. Mitchell, Joanne M. Monks, Susan N. Keall, Joanna N. Wilson, Nicola J. Nelson Apr 2014

Sex Ratio Bias And Extinction Risk In An Isolated Population Of Tuatara (Sphenodon Punctatus), Kristine L. Grayson, Nicola J. Mitchell, Joanne M. Monks, Susan N. Keall, Joanna N. Wilson, Nicola J. Nelson

Biology Faculty Publications

Understanding the mechanisms underlying population declines is critical for preventing the extinction of endangered populations. Positive feedbacks can hasten the process of collapse and create an ‘extinction vortex,’ particularly in small, isolated populations. We provide a case study of a male-biased sex ratio creating the conditions for extinction in a natural population of tuatara (Sphenodon punctatus) on North Brother Island in the Cook Strait of New Zealand. We combine data from long term mark-recapture surveys, updated model estimates of hatchling sex ratio, and population viability modeling to measure the impacts of sex ratio skew. Results from the mark-recapture surveys show ...


Revision Of Anacaena Thomson, 1859 Xi. Republic Of The Philippines (Coleoptera: Hydrophilidae), Hendrik Freitag Jan 2014

Revision Of Anacaena Thomson, 1859 Xi. Republic Of The Philippines (Coleoptera: Hydrophilidae), Hendrik Freitag

Biology Faculty Publications

The species of Anacaena THOMSON, 1859 (Coleoptera: Hydrophilidae) of the Republic of the Philippines are revised. Fifteen new species are described: Anacaena albay sp.n., A. amplocomata sp.n., A. apo sp.n., A. balabag sp.n., A. cordillera sp.n., A. davao sp.n., A. destructa sp.n., A. emergens sp.n., A. hemisphaerica sp.n., A. levistriata sp.n., A. philippina sp.n., A. princesa sp.n., A. quezona sp.n., A. sulcata sp.n., and A. zamboangana. All species are endemic to the Philippines, twelve are aquatic, the habitat of three species is unknown. All Philippine species ...


A Mega-Diverse Water Beetle Genus (Coleoptera: Hydraenidae: Hydraena Kugelann) Commonly Overlooked In Southeast Asia And Its Potential Use For Environmental Biomonitoring, Hendrik Freitag Jan 2014

A Mega-Diverse Water Beetle Genus (Coleoptera: Hydraenidae: Hydraena Kugelann) Commonly Overlooked In Southeast Asia And Its Potential Use For Environmental Biomonitoring, Hendrik Freitag

Biology Faculty Publications

This study summarizes the current knowledge of the water beetle genus Hydraena Kugelann in Southeast Asia. The surprising species diversity and endemism rates in Hydraenopsis Janssens, the only subgenus present in Southeast Asia, are discussed. Data of five published Hydraena surveys from the Philippines and Singapore are used to evaluate species richness and the occurrence of species assemblages that are subject to the presence and quality of forests. Species richness was found to be generally higher in old grown forests. Some species appeared to be confined to near-natural forests. The denomination of indicator species is impeded by adequate sampling data ...