Wild gorillas signal using odor.
Silverback gorillas appear to use odor as a form of communication to other gorillas, according to a study published July 9, 2014 in the open-access journal PLOS ONE by Michelle Klailova from University of Stirling, UK, and colleagues.
Mammals communicate socially through visual, auditory, and chemical signals. The chemical sense is in fact the oldest sense, shared by all organisms including bacteria, and mounting evidence suggests that humans also participate in social chemical signaling. However, not much is known about this type of signaling in closely related hominoids, like wild apes. To better understand chemical -communication in apes, scientists in this study analyzed odor strength in relation to arousal levels in a wild group of western lowland gorillas in the Central African Republic, specifically focusing on the male silverback, or the mature leader of the group. Scientists determined the factors that predicted extreme levels of odor emission from the silverback. They hypothesized that if gorilla scent were being used as a social signal, instead of only a sign of arousal or stress, odor emission would depend on social context and would vary depending on the gorilla’s relationship to other gorillas.
According to the results, the male silverback may use odor as a modifiable form of social communication, where context-specific chemical-signals may moderate the social behaviors of other gorillas. The authors predicted extreme silverback odor, where the odor was the only element that could be smelled in the surrounding air, by the presence and intensity of interactions between different gorilla groups such as silverback anger, distress and long-calling auditory rates, and the absence of close proximity between the silverback and the mother of the youngest infant. The authors suggest that odor communication between apes may be especially useful in Central African forests, where limited visibility may necessitate increased reliance on other senses.
Michelle Klailova added, “No study has yet investigated the presence and extent to which chemo–communication may moderate behaviour in non-human great apes. We provide crucial ancestral links to human chemo-signaling, bridge the gap between Old World monkey and human chemo-communication, and offer compelling evidence that olfactory communication in hominoids is much more important than traditionally thought.” Read more…
Throughout evolution, living things have repeatedly developed physically distinct sexes, but how does this actually happen? A discovery in the multicellular green alga, Volvox carteri, has revealed the genetic origin of male and female sexes, showing how they evolved from a more primitive mating system in a single-celled relative.
A team of scientists led by James Umen, Ph.D. , Associate Member, Enterprise Institute for Renewable Fuels at the Danforth Plant Science Center, identified the master regulatory gene for sex determination in Volvox and found that it has acquired new functions compared to a related gene in its close relative, the unicellular alga Chlamydomonas reinhardtii, which does not have physically distinguishable (dimorphic) sexes. Their findings are publishing in the open access journal PLOS Biology on July 8, and may also provide a possible blueprint for how sexes in other multicellular organisms like plants and animals may have originated.
For plants and animals having male and female reproductive cells or gametes is the norm, and the differences between the two types of gametes are obvious. Male gametes are small motile sperm or pollen, while female gametes are large egg cells. However, the evolutionary origins of male and female sexes are unclear because the distant unicellular relatives of plants, animals and other multicellular species generally don’t have distinct sexes, but instead have mating types – a system in which gametes of one mating type can only fuse with those with a different mating type, but the cells of each mating type are indistinguishable from each other in size and morphology. Read more…
Melbourne researchers are homing in on a new target for malaria treatment, after developing a compound that blocks the action of a key ‘gatekeeper’ enzyme essential for malaria parasite survival.
The compound, called WEHI-916, is the first step toward a new class of antimalarial drugs that could cure and prevent malaria infections caused by all species of the parasite, including those resistant to existing drugs.
Scientists at the Walter and Eliza Hall Institute developed WEHI-916 to block the critical malaria enzyme Plasmepsin V. The research team has previously shown Plasmepsin V is a ‘gatekeeper’ enzyme responsible for controlling the transport of critical proteins in and out of the parasite. Read more…
A group of researchers from the US has moved a step closer to preventing infections of the common hospital pathogen, Staphylococcus aureus, by revealing the mechanisms that allow the bacteria to rapidly clog up medical devices.
New Journal of Physics
In a study published today, 27 June, in the Institute of Physics and German Physical Society’s New Journal of Physics, the researchers have shown that the bacteria colonizes into large groups, called biofilms, using a biological glue, and form thin, slimy, thread-like structures called streamers.
The streamers adhere to a surface and are able to trap passing cells as they flow through medical devices such as stents and catheters, becoming more rigid and eventually clogging up the whole device.
In their study, the researchers, from Princeton University, recreated the physical environments of medical devices with curvy channels, multiple networks and a flowing fluid, and showed that streamers can rapidly expand and create a blockage in a surprisingly short space of time. Read more…
Antibodies and their derivatives can protect plants and animals—including humans—against viruses. Members of this class of drugs are usually highly specific against components of a particular virus, and mutations in the virus that change these components can make them ineffective. An article published on June 26th in PLOS Pathogens now reports that a mini antibody called 3D8 scFv can degrade (or chew up) viral DNA and RNA regardless of specific sequences and protect mammalian cells and genetically manipulated mice against different viruses. Read more…