Pygmy slow twins born 9 April, male and female, dam is Sovanni, sire Pygmy Hunter who tragically passed away (peacefully in his sleep of natural causes!) 4 April, never having the opportunity to meet his adorable twins.

But his legacy lives on!

 

A recently released conservation oriented film by the BBC, which features DLC’s own Dr. Erik Patel, has just won accolades at the International Wildlife Film Festival in Missoula, Montana! http://wildlifefilms.wordpress.com/  In addition to Erik’s research on silky sifakas, “Madagascar, Lemurs, and Spies” also features undercover work by Sascha Von Bismarck of the Environmental Investigation Agency, on the illegal precious wood trade in Madagascar. The film won the following awards: Best in category of conservation, Best conservation message, and Merit for cinematography. The film was shot mostly in northeastern Madagascar, including forest footage in Marojejy National Park, within the SAVA region covered by our DLC conservation initiative that is led by Erik.

“Madagascar, Lemurs, and Spies has shown in the UK (March) and will no doubt at some point appear on US television, so keep an eye out! For more information on the film go to http://www.bbc.co.uk/programmes/b01dlcgk

Aracus started getting into trouble as a youth, with a string of arrests, rehab, and finally a stint in lock-up.  He never knew who his father was.  While he was confined, he began participating in research projects, and discovered he really had a talent for it.  Upon release, he settled down with a couple of female roommates, and now supports his growing family with his research endeavours.

Aracus is a ringtailed lemur.  He’s 20 now, and all his life, records have been kept – medical records, weights, dates, but also screeds of descriptive records, that reflect the richness and texture of his life.  The question is – how to make all these records available in a way that they can be used to increase our understanding of these interesting andcomplex animals.

Duke Lemur Center was founded in 1966, and ever since the earliest days, researchers and technicians have kept meticulous records.  For the first 30-odd years, records were hand-written or typed on paper, until the first computerised databases in the mid-1990s.  These contain medical and husbandry records, but the databases are cumbersome and not particularly user-friendly.  There are also excel files, and text files with descriptive records.  All these records represent a huge and valuable resource, but they are largely inaccessible without a great deal of work.

Until now, that is! Dr Sarah Zehr, former research manager at the DLC, has taken on the enormous task of assessing and assembling the information from all these sources into an analysable format. Data for 4,000 animals and 30 lemur species will be included in the database, which the scientists among you will appreciate – large sample sizes give statistically reliable results.  Basic information such as animal identification, birth and death dates, parents, weights at birth and through life, housing and diets will be included, along with variables that are anecdotal at present, such as litter size, length of gestation, and susceptibility to disease.

With such disparate sources, a lot of work is going into ensuring that the data is reliable and “good” and this could not be accomplished without valuable input from DLC staff and other experts.  There is more than 45 years worth of data, so it is quite a task, but Sarah finds it very satisfying. “The need for this data is obvious, it has immediate and direct application for a lot of things”, says Sarah.  “People need and want this data.”

The project began in January 2012, and is funded by the National Evolutionary Synthesis Center (NESCent), the DLC, and Duke Natural Sciences for a year.   After this, large amounts of the data will be made publically available through NESCent.  Once the database is up and running, the treasure hunt can begin!

Photos by Richard Roach (top) and David Haring (below).

The theory is that leaping from branch to branch uses more energy than reaching across, so a lemur will try to bridge the gap until it is no longer able to do so. However, different types of spines are better at different activities. For instance, blue-eyed black lemurs have flexible, mobile spines that are better for leaping. Lorises have relatively rigid spines that work like cranes and these lemurs are expected to be able to bridge longer gaps.

To test this, Michael and the two member team that is the Research Department are clustered in the research room at the Lemur Center, peering intently at a lone blue-eyed black lemur running back and forth across a couple of wooden poles that are separated at the center by a short gap. The set-up is meant to emulate a terminal branch environment, and Tarantino the lemur is enticed to cross from “branch” to “branch” by means of a raisin dropped into a metal bowl. He seems to enjoy this activity – after a while he doesn’t bother to wait for the “plink” of a raisin into the bowl before turning and racing back across the “branches”.

The gap-end of one of the poles is attached to a super-sensitive scale that measures the movement of the lemur in 3D as it bridges the gap between the poles. It looks like Tarantino is moving non-stop from one end of the pole to the other across the gap but Michael shows us a graph on the computer screen that tells us that Tarantino has braked as he notices the gap, moved from side to side, and accelerated as he crosses to the other side. At the same time, two video cameras are recording Tarantino’s movements for later analysis in slow motion. He has white dots of non-toxic paint strategically located on his limbs so that a 3D picture can be built up of the way he moves.

http://www.youtube.com/watch?v=hDZnlR5v-gY

As the trials progress, the gap will be widened, until the point where the lemur no longer bridges the gap but has to leap instead. Eventually, flexible, wobbly ends will be attached at the gap, more like real branches and other lemur species will be tested, including three species of Loris, and fat-tailed dwarf lemurs.

http://sites.duke.edu/dukeresearch/2012/03/20/meet-joel-bray-lemur-enthusiast/

Ringtail lemurs live in large social groups of 20 – 30 individuals in the wild, and during the breeding season, there is a lot of competition between the males to breed with the females. They have a useful way of resolving conflicts that doesn’t involve the risk of injury – the Stink Fight.

Male ringtails have scent glands on their wrists and shoulders. The wrist gland produces a volatile, short-lived odor, while the shoulder gland produces a brown toothpaste-like substance, which is much longer lasting. A stink fight begins when two male lemurs face off and pull their tails through these two glands, then wave or flick their tails at each other, to waft their “fragrance” towards their rival. Stink fights last until one lemur backs off, and can be resolved fairly quickly, but these smelly stand-offs have also been reported to last up to an hour.

Stink fights are not just for breeding season though, and not just for other lemurs. Researcher Katie Grogan places wooden poles smeared with grape jelly or lemur odors into lemur enclosures in order to determine if a lemur prefers the scent of one lemur over another, and she is used to the lemurs scent- marking the poles. She realised the extent of the possessive feelings of one male lemur, however, when he stink fought her as she tried to take a pole out of his enclosure. Sadly for the lemur, and probably luckily for Katie, the human sense of smell is not sensitive enough to detect the odor!

Author: Mel Norris, DLC Volunteer

http://www.bbc.co.uk/programmes/b01dlcgk

Fast forward to the present, and here I sit in London, still studying the genes of mouse lemurs.  Since that fateful day nearly 15 years ago, field activities and science have forged ahead, and it is now generally acknowledged that there are almost certainly 16 or more species of mouse lemurs!  Although most of the early evidence for this proliferation in species numbers has come from genetic data, scientists are delving ever deeper into the question of mouse lemur biodiversity, finding that mouse lemur species have subtle preferences for different foods and ecotypes, and also, that the males sing different species-specific mating calls to the females — much like is the case with various birds and insects.  As for me, I am stillstuck on the genetic side of things, and accordingly, I am looking into a set of genes that allow mouse lemurs (and other vertebrates) to recognize a rich bouquet of pheromones.  The thinking goes something like this:

  As mouse lemurs species begin to diverge from one another, the members of the diverging species need to be able to recognize same-species partners from different-species partners. Theoretically, divergent pheromone signals might be a good way to do this.  Following this logic, natural selection will favor those individuals who are best able to discriminate same-species pheromones from those of different-species pheromones, which will then promote a process wherein there are more and more elaborate families of pheromone receptor genes.  So finally, we come to our hypothesis:  mouse lemurs (and perhaps, other nocturnal lemurs) will have considerably more elaborate pheromone receptor gene families than the other lemurs — or maybe not!  Stay tuned as my colleagues and I try to figure it all out.  Updates will follow!

- Dr. Anne D. Yoder

Director, Duke Lemur Center

Sadly, this will be the last infant for Rupi and Tiberius, as they are calling it quits as a breeding pair (although they will of course remain friends assuming Tiberius remains adequately subservient).   But their break up (no pun intended) is not really their choice, as Tiberius has had two broken bones the last couple of years, apparently from falls while tree hopping in NHE 7.  Since Rupi’s group is free ranging, Tiberius is just going to have to find (or be assigned to) a more sedentary mate. 

The one bit of sad news this birth season, was that Drusilla (free ranging in the warmer months in NHE 8) delivered a stillborn infant on January 30^th.  The last couple of years Drusilla has started to have problems delivering infants, in large part due to their extremely large parts.  This latest was a whopping140 grams, largest ever reported birthweight for a sifaka. 

The really great news about this sifaka birth season is that two out of three infants born at DLC are female, and our in house sifaka population now stands at 14 males and 13 females, its healthiest ratio in years! 

For whatever reason, sifaka birth season seems to be becoming less spread out over a period of two or more months, and births are seemingly starting to clump into a shorter time span.  This past birth season (including the four institution where DLC sifaka are on loan) there were seven births in January (most ever in a single month) and only one outside of January (in early February to a pair on loan at Sacramento).