Friday, May 24, 2019

Chimpanzees Menu Includes Tortoises

Chimpanzees found to be eating tortoises after breaking their shells on tree trunks.

An international team of researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig and the University of Osnabrück, Germany, have observed wild chimpanzees in the Loango National Park, Gabon, eating tortoises. They describe the first observations of this potentially cultural behavior where chimpanzees hit tortoises against tree trunks until the tortoises’ shells break open and then feed on the meat.


Chimpanzee at Loango National Park in Gabon feeding on tortoise meat.

Credit: © Erwan Theleste

"We have known for decades that chimpanzees feed on meat from a variety of animal species, but until now the consumption of reptiles has not been observed", says Tobias Deschner, a primatologist at the Max Planck Institute for Evolutionary Anthropology. "What is particularly interesting is that they use a percussive technique that they normally employ to open hard-shelled fruits to gain access to meat of an animal that is almost inaccessible for any other predator".

The researchers studied the behaviour of chimpanzees of the newly habituated Rekambo community. They observed 38 prey events by ten different chimpanzees in the dry season, a period when other preferred food such as fruits is abundant. "Sometimes, younger animals or females were unable to crack open the tortoise on their own. They then regularly handed the tortoise over to a stronger male who cracked the tortoise’s shell open and shared the meat with all other individuals present", says Simone Pika, first author of the study and a cognitive scientist at the University of Osnabrück.

Leftovers from dinner


Credit: MaxPlanckSociety


There was one exceptional case in which an adult male, who was on his own, cracked a tortoise, ate half of it up while sitting in a tree and then tucked the rest of it in a tree fork. He climbed down, built his nest in a nearby tree and came back the next morning to retrieve the leftovers and continue to feast on them for breakfast. "This indicates that chimpanzees may plan for the future", says Pika. "The ability to plan for a future need, such as for instance hunger, has so far only been shown in non-human animals in experimental and/or captive settings. Many scholars still believe that future-oriented cognition is a uniquely human ability. Our findings thus suggest that even after decades of research, we have not yet grasped the full complexity of chimpanzees’ intelligence and flexibility".

Deschner adds: "Wild chimpanzee behaviour has been studied now for more than 50 years and at more than ten long-term field sites all across tropical Africa. It is fascinating that we can still discover completely new facets of the behavioural repertoire of this species as soon as we start studying a new population".

The authors further emphasize the importance of non-human primate field observations to inform theories of hominin evolution. "As one of our closest living relatives, the study of chimpanzee behaviour is a window into our own history and evolution", says Pika. "To prevent this window from closing once and for all, we need to do whatever we can to secure the survival of these fascinating animals in their natural habitats across Africa", concludes Deschner.





Contacts and sources:
Prof. Dr. Simone Pika, Sandra Jacob
Max Planck Institute for Evolutionary Anthropology
Citation: Wild chimpanzees (Pan troglodytes troglodytes) exploit tortoises (Kinixys erosa) via percussive technology.
Simone Pika, Harmonie Klein, Sarah Bunel, Pauline Baas, Erwan Théleste, Tobias Deschner. Scientific Reports, 2019; 9 (1) DOI: 10.1038/s41598-019-43301-8



The Beer of Pharaohs and Drunken Philistines Recreated with Ancient Yeast

What kind of beer did the Pharaohs drink? In ancient times, beer was an important ingredient in people's daily diet. Great powers were attributed to beer in the ancient world, particularly for religious worship and healing properties.

Israeli scientists resurrected yeast from ancient beer jugs to recreate a 5,000-year-old brew.

The pottery used to produce beer in antiquity served as the basis for this new research. The research was led by Dr. Ronen Hazan and Dr. Michael Klutstein, microbiologists from the School of Dental Medicine at the Hebrew University of Jerusalem (HUJI). They examined the colonies of yeast that formed and settled in the pottery's nano-pores. Ultimately, they were able to resurrect this yeast to create a high-quality beer...that's approximately 5,000 years old.

Beer cruse from Tel Tzafit/Gath archaeological digs, from which Philistine beer was produced.

Credit:  Yaniv Berman/Israel Antiquities Authority.


Many cooks were invited into this'beer kitchen to isolate the yeast specimens from the ancient debris and to create a beer with it. First the scientists reached out to vintners at Kadma Winery. This winery still produces wine in clay vessels, proving that yeast may be safely removed from pottery, even if it had lain dormant in the sun for years.

The yeast was then photographed by Dr. Tziona Ben-Gedalya at Ariel University's Eastern R&D Center. Following her initial examination, the team reached out to archaeologists Dr. Yitzhak Paz from the Israel Antiquities Authority (IAI), Professor Aren Maeir at Bar Ilan University and Professors Yuval Gadot and Oded Lipschits from Tel Aviv University. These archaeologists gave them shards of pottery that had been used as beer and mead (honey wine) jugs back in ancient times--and miraculously, still had yeast specimens stuck inside. These jars date back to the reign of Egyptian Pharaoh Narmer (roughly 3000 BCE), to Aramean King Hazael (800 BCE) and to Prophet Nehemiah (400 BCE) who, according to the bible, governed Judea under Persian rule.

The researchers, with the help of HUJI student Tzemach Aouizerat, cleaned and sequenced the full genome of each yeast specimen and turned them over to Dr. Amir Szitenberg at the Dead Sea-Arava Science Center for analysis. Szitenberg found that these 5,000-year yeast cultures are similar to those used in traditional African brews, such as the Ethiopian honey wine tej, and to modern beer yeast.


L'chaim! The Israeli research team samples their ancient brew.

Credit: Yaniv Berman, Israel Antiquities Authority.


Now it was time to recreate the ancient brew. Local Israeli beer expert Itai Gutman helped the scientists make the beer and the brew was sampled by Ariel University's Dr. Elyashiv Drori, as well as by certified tasters from the International Beer Judge Certification Program (BJCP), under the direction of brewer and Biratenu owner Shmuel Nakai. The testers gave the beer a thumbs up, deeming it high-quality and safe for consumption.

Dr. Ronen Hazan, Hebrew University-Hadassah School of Dental Medicine: "The greatest wonder here is that the yeast colonies survived within the vessel for thousands of years--just waiting to be excavated and grown. This ancient yeast allowed us to create beer that lets us know what ancient Philistine and Egyptian beer tasted like. By the way, the beer isn't bad. Aside from the gimmick of drinking beer from the time of King Pharaoh, this research is extremely important to the field of experimental archaeology--a field that seeks to reconstruct the past. Our research offers new tools to examine ancient methods, and enables us to taste the flavors of the past."

Dr. Yitzchak Paz, Israel Antiquities Authority: "We are talking about a real breakthrough here. This is the first time we succeeded in producing ancient alcohol from ancient yeast. In other words, from the original substances from which alcohol was produced. This has never been done before."

Prof. Yuval Gadot, Tel Aviv University's Department of Archaeology and Ancient Near Eastern Cultures: "We dug at Ramat Rachel, the largest Persian site in the Judaean kingdom, and found a large concentration of jugs with the letters J, H, D - Yahud - written on them. In a royal site like Ramat Rachel it makes sense that alcohol would be consumed at the home of the Persian governor."

Prof. Aren Maeir, Bar-Ilan University's Department of Land of Israel Studies and Archaeology: "These findings paint a portrait that supports the biblical image of drunken Philistines."


Contacts and sources:
Tali Aronsky
Hebrew University of Jerusalem

Citation: Isolation and Characterization of Live Yeast Cells from Ancient Vessels as a Tool in Bio-Archaeology Tzemach Aouizerat, Itai Gutman, Yitzhak Paz, Aren M. Maeir, Yuval Gadot, Daniel Gelman, Amir Szitenberg, Elyashiv Drori, Ania Pinku https://mbio.asm.org/content/10/2/e00388-19 http://dx.doi.org/10.1128/mBio.00388-19