The agile gibbon, Hylobates agilis, is a species of Old-World primate also known as the black-handed gibbon. It is found in Sumatra southeast of Lake Toba and Singkil River, in a small area on the Malay Peninsula, and south Thailand near the Malaysian border. They predominantly live in rainforests where their long arms help them swing from branch to branch with ease.
Gibbon pairs are monogamous, whereby mated pairs stay together until one mate dies. The species becomes sexually mature around 8 years of age. The gestation period is around 7 months. Agile gibbons give birth to a single offspring per pregnancy, and around 5-6 offspring during their lifetime. The female gibbons care for their offspring until they are around 2 years old. Males participate in parental care grooming offspring and helping defend them.
Agile gibbons are highly vocal, using their vocalizations to defend their territories from other mated pairs. This is known as “singing” where in the early morning great calls can be heard, often as duets, as a way of claiming home territory. When singing is not enough the pairs will chase intruders away.
Hylobates agilis is listed as "endangered" by IUCN, the key reasons being deforestation leading to loss of habitat. Conservation measures such as breeding programs and reserve game parks have been implemented to combat the species decline, but it is yet to be seen if the measures are to be effective.
Today we share a $1K chromosome-length assembly for the agile gibbon (cN50=36kb; sN50=94Mb), generated using samples donated by Susie, an agile gibbon from the Houston Zoo. Check out this photo of her created by Joel Sartore for the National Geographic Photo Ark!
Check out below how the 22 chromosomes of the new assembly relate to those of humans. The whole-genome alignment plot suggests multiple rearrangements, in agreement with the previously noted propensity for unusually high number of large-scale chromosomal rearrangements in gibbons in comparison to the inferred ancestral ape karyotype . Given the relatively recent differentiation of these genera (4–6 million years ago (Myr ago), this constitutes an extraordinarily fast rate of karyotype change. Check out the exciting work by Carbone et al., Nature 2014 for the investigation of possible causes in the white-cheeked gibbon Nomascus leucogenys. We look forward to using the agile gibbon genome assembly to investigate the question further.
Browse below the interactive contact map for the agile gibbon and don't forget to visit the corresponding assembly page for more information and details!
We gratefully acknowledge Houston Zoo for providing the sample for this work. We also thank the DNA Zoo Australia team at the University of Western Australia and Pawsey Supercomputing Centre for the computational support for this genome assembly.
Blog by: Ashling Charles, Olga Dudchenko, Parwinder Kaur