I have a new favourite animal. These are pictures of baby Bonobos and they are the cutest things in the world. Bonobo apes are arguably the most human creature on the planet and are absolute sweethearts. I’d give anything to meet one up close and personal.
They are also much more placid than the unpredictable and sometimes violent Common Chimpanzee.
Although emerging evidence suggests that transposable elements (TEs) have contributed novel regulatory elements to the human genome, their global impact on transcriptional networks remains largely uncharacterized. Here we show that TEs have contributed to the human genome nearly half of its active elements. Using DNase I hypersensitivity data sets from ENCODE in normal, embryonic, and cancer cells, we found that 44% of open chromatin regions were in TEs and that this proportion reached 63% for primate-specific regions. We also showed that distinct subfamilies of endogenous retroviruses (ERVs) contributed significantly more accessible regions than expected by chance, with up to 80% of their instances in open chromatin. Based on these results, we further characterized 2,150 TE subfamily–transcription factor pairs that were bound in vivo or enriched for specific binding motifs, and observed that TEs contributing to open chromatin had higher levels of sequence conservation. We also showed that thousands of ERV–derived sequences were activated in a cell type–specific manner, especially in embryonic and cancer cells, and we demonstrated that this activity was associated with cell type–specific expression of neighboring genes. Taken together, these results demonstrate that TEs, and in particular ERVs, have contributed hundreds of thousands of novel regulatory elements to the primate lineage and reshaped the human transcriptional landscape” (read more/open access).
- Illustration by Michael Boardman, Coyote Graphics,© Conservation InternationalClick through the image to learn “about these primates’ behaviors, habitats, and physical characteristics. Just roll your cursor over the different primates, and click on ones that you would like to know more about.”
A tarsier (Bill Bailey’s Jungle Hero - BBC)
Siamang Head Stand Agile siamangs and orangutans share habitat in the wild, and get along beautifully at the Zoo too.
Previously, the only primate thought to hibernate was the western fat-tailed dwarf lemur. But in a new study, out of Duke University, suggests that Crossley’s dwarf lemur and Sibree’s dwarf lemur also burrow into the ground and spend three to seven months hibernating.
“Exactly what triggers hibernation is still an open question,” said lead author Marina Blanco a postdoctoral researcher at the Duke Lemur Center.
Unlike animals such as bears and ground squirrels, which hibernate to survive the cold, western dwarf lemurs hibernate to survive during western Madagascar’s long dry season — a time when temperatures top 85 degrees, trees drop their leaves and food and water are in short supply.
To find out more, Blanco and her colleagues trapped and fitted the squirrel-sized animals with temperature-sensitive radio collars before the start of the hibernation season, allowing them to find the lemurs’ underground burrows and monitor their body temperature once hibernation began.
“To the casual observer, it looks for all the world as if the animals are dead. Their bodies are cold, they are utterly still and they take a breath only once every several minutes or so,” said co-author Anne Yoder, director of the Duke Lemur Center.
Western dwarf lemurs hibernate in drafty tree holes, where their body temperature fluctuates by as much as 20 degrees with the outside air. But the researchers found that eastern dwarf lemurs keep their body temperatures more constant in cozy underground burrows.
Photo: Eastern dwarf lemur hibernating in its underground burrow in Madagascar. (Credit: Image courtesy of Duke University) and Mary Bates
Journal Reference: Marina B. Blanco, Kathrin H. Dausmann, Jean F. Ranaivoarisoa, Anne D. Yoder. Underground hibernation in a primate. Scientific Reports, 2013; 3 DOI:10.1038/srep01768
- Images and text by artist Russell Dempster
“I was approached a while back by Edinburgh Zoo to design ‘My Primate Family Tree’ for the Living Links department of the zoo. It was to be an educational mural to show a few representatives from the hundreds of living primates, and tell us how closely related we are to each with the bonus of being able to take part in the picture and then completing the link. It fills an outside space of 2.3m x 3m. Every monkey and ape was drawn individually and all pieced together at the final artwork stage and then printed onto 3 panels.
The base of the tree represents the evolutionary origin of primates about 65 million years ago. The Capuchin and Squirrel monkeys on the bottom left represent the primates of the ‘New World’ (The Americas) that split from other evolving primates about 35 million years ago. Next, the Gelada Baboon, Japanese Macaque and Diana Monkey on the top left represent the ‘Old World’ monkeys of Africa and Asia that split from the apes shown on the right about 25 million years ago. Our closest relative is the Chimpanzee, then it’s the Gorilla and then the Orang-utan. These great apes and ourselves are a family that share a common ancestor about 14 million years ago.”
For more information about the divergence of humans and apes see:
- Langergraber, K.E. et al. 2012. “Generation times in wild chimpanzees and gorillas suggest earlier divergence times in great ape and human evolution,” PNAS 109(39):15716–15721
- Pontzer, H. 2012. ”Overview of Hominin Evolution,” Nature Education Knowledge 3(10):8 (open access)
Photograph: 2013 Whitley Awards
Drill baby drill! The fate of African biodiversity and the monkey you’ve never heard of
Commentary by: Zach Fitzner
Equatorial Guinea is not a country that stands very large in the American consciousness. In fact most Americans think you mean Papua New Guinea when you mention it or are simply baffled. When I left for Bioko Island in Equatorial Guinea, I also knew almost nothing about the island, the nation, or the Bioko drills (Mandrillus leucophaeus poensis). The subspecies of drill is unique to Bioko Island and encountering them was an equally unique experience. I initially went to Bioko as a turtle research assistant but ended up falling in love with the entire ecosystem, especially the Bioko drills as I tagged along with drill researchers.
Bioko itself looks a bit like a bean; if the bean was 779 square miles, made out of dormant volcanoes, covered in lush rainforest and floating in the Atlantic off Africa’s west coast that is. The island is part of the Cameroonian line, a chain of dormant volcanoes extending west from the mainland. Ten thousand years ago rising sea levels cut off a peninsula, creating Bioko, which is the main island of Equatorial Guinea, a small Spanish-speaking nation in equatorial, western Africa. Bioko has a population of about 260,000 spread throughout some 26 cities arranged mostly near the coast.
But Bioko is also a refuge for wildlife, including seven species of monkey and eleven subspecies, hidden away in the rough interior of the island. Wildlife biodiversity and endemism (species found only on the island) are high because Bioko is in the tropics, and an island with a relatively low human population. The Bioko drill is arguably the island’s flagship species…
(read more: MongaBay) (photos: Drill Films)
“Chimpanzees don’t eat fish. They don’t even swim. But at Lake Tanganyika in western Tanzania, scientists have found that to save chimps, they must look underwater. That’s because here, everything—people, fish, water, forest, and chimps—is interconnected. Attempting to conserve the apes without accounting for the health of the fishery that provides food and income for local people would doom these efforts.
Today, fish supplies are dwindling, villages are growing fast and chimps are getting squeezed into smaller and smaller forests. Understanding these connections means understanding Lake Tanganyika. It is the second largest lake by volume in the world, and the longest. It contains an estimated 16 to 17 percent of the world’s freshwater supply.
The lake is rich in fish, and even if you’ve never been there, they might look oddly familiar: Many of the colorful fish that swim around American aquariums originated in Lake Tanganyika. More than 200 species are found nowhere else on earth.
“The fish communities have been isolated in this lake for millions of years,” says Colin Apse, senior freshwater conservation advisor for The Nature Conservancy. “It’s one of the last large lakes in the world that still has an intact aquatic ecosystem. It’s not dominated by non-native fish. Many biologists recognize it as an evolutionary laboratory with a really amazing set of species.”
And not only fish: the lake is home to mollusks, snails, crabs, shrimp and even jellyfish that you might expect to find in an ocean. “You can go snorkeling here and feel like you’re on a coral reef,” says Apse. But this is more than an underwater attraction. This amazing diversity provides food and jobs for literally hundreds of thousands of people. Fish from Lake Tanganyika provide one-third of the protein for people who live along the lake.
“Many people don’t realize how important freshwater fishes are as a protein source globally,” says Apse. “Often, freshwater fisheries are ignored until it’s too late. When people think of conservation in Africa, they often think of large, well-known mammals like rhinos and cheetahs. But if you look closely, you see that freshwater ecosystems are just as important, for people and for biodiversity. Especially here.” ” (read more).
(Source: The Nature Conservancy)
I was sick this weekend. The kind of sick where your nose runs so much that you begin to question how the human body can produce so much mucus. My throat hurt. I was coughing. But the worst part was the headache: My head felt like it was being continuously squeezed by a vise, or maybe some sort of medieval torture device. The pain was so bad even my teeth hurt. As I was lying in bed next to my half-empty box of Kleenex, I thought, “This wouldn’t be happening if we had descended from Asian, not African, apes.” (Yes, I was really thinking that.)
But before I explain what apes have to do with my cold, let’s cover some basic biology. When the cold virus (or bacteria or an allergen like ragweed) enters the body, the nose produces mucus to prevent an infection from spreading to the lungs. This results in a runny nose. All of the extra snot can also plug up passages that connect the nose to air-filled pockets in the bones of the skull, called sinuses. Sinuses produce their own mucus and are thought to help humidify air, as well as stabilize and strengthen the skull. But when the passageways between the head’s sinuses and nasal cavity get blocked, the sinuses’ mucus can’t drain and the air pockets fill, causing pressure to build . Sometimes the lining of the sinuses swell, which results in the further production of mucus and build-up of pressure. That pressure hurts.
Humans have four types of sinuses that play a role in sinus headaches: the frontal sinus in the forehead, the maxillary sinus in the cheeks, the ethmoid sinus between the eyes and the sphenoid sinus behind the nose. The African apes, gorillas and chimpanzees, have all four of these sinuses. The Asian apes, orangutans and gibbons (the so-called lesser apes because of their smaller size), have just two, lacking the ethmoid and frontal sinuses.
The ethmoid and frontal sinuses can be traced back at least 33 million years ago to a primate called Aegyptopithecus that lived in Africa before the ape and Old World monkey lineages originated. (Old World monkeys are those that live in Africa and Asia.) These sinuses have also been found in some of the earliest known apes, such as the roughly 20-million-year-old Morotopithecus and 18-million-year-old Afropithecus, both from Africa. Chimpanzees, gorillas and humans inherited these sinuses from the most ancient apes. Gibbons and orangutans, however, each lost these sinuses independently after they diverged from the rest of the apes; gibbons evolved about 18 million years ago while orangutans split from the other great apes roughly 15 million years ago.
It’s not clear why the Asian apes lost the ethmoid and frontal sinuses. In the case of the orangutan, the animal has a much more narrow space between its eyes and a more severely sloped, concave forehead than the African great apes. So there just may not be room for these air pockets to form.
But gibbons and orangutans do still have the maxillary and sphenoid sinuses, which are enough to cause annoying pain and headaches. So I should really apologize to my African ape ancestors. Clearly, I had some misdirected anger. I should have been mad at the virus that invaded my body.