Tardigrades’ genes help them survive extreme conditions
Tardigrades are microscopic animals that can withstand complete dehydration, resurrecting years later when water is again available. To investigate the genes underlying their extraordinary ability to survive in extreme conditions, researchers analyzed the DNA code for two tardigrade species and published their study in PLOS Biology.
The researchers identified the genes that enable tardigrades to resist desiccation when they’re dehydrated. When tardigrades are drying out, certain genes are turned on, and these genes carry sets of proteins that appear to replace the water that their cells lose, helping to preserve the microscopic structure until water is available again. Professor Mark Blaxter says, “This is just the start — with the DNA blueprint we can now find out how tardigrades resist extremes, and perhaps use their special proteins in biotechnology and medical applications.”
Women and children also exposed to hunting-related pathogens
Hunting, slaughtering and cooking of wild animals in West and Central Africa can put humans at risk of contracting animal-borne infections such as Ebola virus and Lassa virus, and scientists have investigated how to educate those involved to minimize risks. While previous interventions have mostly focused on adult men, a new study from PLOS Neglected Tropical Diseases found that women and children also participate in these activities and need to be considered in intervention strategies.
The researchers spent four months in Bo City, the second largest city in Sierra Leone, and nine surrounding rural villages. They conducted interviews and focus groups, assigned essays and observed study participants to understand interactions between humans and animals in the area. They found that children were often involved in communal hunts, with boys often starting to hunt alone and in groups around age 7. Men, women and children were all involved in preparing and cooking meat, which was always handled with bare hands. The researchers suggest that “intervention strategies should become more diversified and context-specific. In particular, the role of children should be recognized; specific intervention strategies should be tailored to children’s specific hunting practices.”
Isotopes in Neolithic cattle teeth suggest a variety of herding strategies
Secondary products from cattle such as milk, manure and animal power became increasingly important over the course of the Neolithic, leading to larger herds and increasing demand for grazing resources. To find out what herding strategies may have been used by early Europeans during this period, researchers analyzed strontium isotopes in cattle teeth found in a Neolithic settlement (occupied 3384–3370 BC) in present-day Switzerland. They published their study in PLOS ONE.
Strontium signatures reflect local soil and plants, and can vary over relatively short distances, so their patterns may suggest different herding strategies. The researchers found three distinct patterns that indicated local cattle herding, seasonal herding and year-round herding away from the site. These three herding strategies were not uniformly represented in various areas of the settlement, which suggests unequal access to the most favorable grazing grounds. Therefore, the increasing importance of cattle may have contributed to social inequalities between groups or households, promoting social stratification into the European Bronze Age.
Image Credit: Kazuharu Arakawa and Hiroki Higashiyama
Yoshida Y, Koutsovoulos G, Laetsch DR, Stevens L, Kumar S, Horikawa DD, et al. (2017) Comparative genomics of the tardigrades Hypsibius dujardini and Ramazzottius varieornatus. PLoS Biol 15(7): e2002266. https://doi.org/10.1371/journal.pbio.2002266
Bonwitt J, Kandeh M, Dawson M, Ansumana R, Sahr F, Kelly AH, et al. (2017) Participation of women and children in hunting activities in Sierra Leone and implications for control of zoonotic infections. PLoS Negl Trop Dis 11(7): e0005699. https://doi.org/10.1371/journal.pntd.0005699
Gerling C, Doppler T, Heyd V, Knipper C, Kuhn T, Lehmann MF, et al. (2017) High-resolution isotopic evidence of specialised cattle herding in the European Neolithic. PLoS ONE12(7): e0180164. https://doi.org/10.1371/journal.pone.0180164