Human ancestor discovery in Ethiopia


This video says about itself:

Becoming Human Documentary

16 December 2013

Humans (variously Homo sapiens and Homo sapiens sapiens) are primates of the family Hominidae, and the only extant species of the genus Homo. Humans are distinguished from other primates by their bipedal locomotion, and especially by their relatively larger brain with its particularly well developed neocortex, prefrontal cortex and temporal lobes, which enable high levels of abstract reasoning, language, problem solving, and culture through social learning. Humans use tools to a much higher degree than any other animal, and are the only extant species known to build fires and cook their food, as well as the only known species to clothe themselves and create and use numerous other technologies and arts. The scientific study of humans is the discipline of anthropology.

Humans are uniquely adept at utilizing systems of symbolic communication such as language and art for self-expression, the exchange of ideas, and organization. Humans create complex social structures composed of many cooperating and competing groups, from families and kinship networks to states. Social interactions between humans have established an extremely wide variety of values, social norms, and rituals, which together form the basis of human society. The human desire to understand and influence their environment, and explain and manipulate phenomena, has been the foundation for the development of science, philosophy, mythology, and religion.

The human lineage diverged from the last common ancestor with its closest living relative, the chimpanzee, some five million years ago, evolving into the australopithecines and eventually the genus Homo. The first Homo species to move out of Africa was Homo erectus, the African variety of which, together with Homo heidelbergensis, is considered to be the immediate ancestor of modern humans. Homo sapiens originated in Africa, where it reached anatomical modernity about 200,000 years ago and began to exhibit full behavioral modernity around 50,000 years ago.

From Science:

Published Online March 4 2015

Early Homo at 2.8 Ma from Ledi-Geraru, Afar, Ethiopia

Abstract

Our understanding of the origin of the genus Homo has been hampered by a limited fossil record in eastern Africa between 2.0 and 3.0 million years ago (Ma). Here we report the discovery of a partial hominin mandible with teeth from the Ledi-Geraru research area, Afar Regional State, Ethiopia, that establishes the presence of Homo at 2.80-2.75 Ma. This specimen combines primitive traits seen in early Australopithecus with derived morphology observed in later Homo, confirming that dentognathic departures from the australopith pattern occurred early in the Homo lineage. The Ledi-Geraru discovery has implications for hypotheses about the timing and place of the origin of the genus Homo.

New monkey species discovery in Brazilian Amazon


This video is called Callicebus modestus — An intimate portrait of an endemic Bolivian primate.

Recently, a relative of Callicebus modestus was discovered.

From BirdLife:

New monkey species discovered in the Amazon Rainforest

By Martin Fowlie, Wed, 04/03/2015 – 10:12

Flaming orange tail and ochre sideburns set new Brazilian monkey apart from its closest relatives.

Scientists have discovered a new species of titi monkey in Brazil, according to a recent paper published in scientific journal Papéis Avulsos de Zoologia.

Titis (genus: Callicebus) are new world monkeys found across South America. These tree-dwelling primates have long, soft fur and live in small family groups consisting of a monogamous pair and their offspring. Rather touchingly, they are often observed sitting or sleeping with their tails entwined.

In 2011, researcher Julio César Dalponte spotted an unusual looking titi monkey on the east bank of the Roosevelt River, whose colouration did not match any known species. Intrigued, a team of scientists supported by the Conservation Leadership Programme headed back into the field to collect the information needed to formally describe what they believed to be a new species.

Over the course of a number of expeditions, the team recorded several groups of these unusual monkeys, whose ochre sideburns, bright orange tail and light grey forehead stripe set them apart from other known species in the genus.

Based on these morphological differences, scientists were able to formally describe the monkey as a new species, which they have named Callicebus miltoni (or Milton’s titi monkey) in honour of Dr Milton Thiago de Mello, a noted Brazilian primatologist who is credited with training many of the country’s top primate experts.

“More than luck”

C. miltoni is found in a small area of lowland rainforest south of the Amazon River in Brazil, and spends most of its time in the upper reaches of the forest, where it feeds on fruits.

Like its close relatives, C. miltoni lives in small groups consisting of a mated pair and their offspring. These groups are territorial and use warning calls to keep others at bay – they are particularly vociferous early in the morning and during the rainy season.

This species is not able to swim or cross mountainous terrain, which means that it is restricted to a small area, effectively hemmed in by a number of rivers and hills. This small range could put the species at risk from human activities, particularly because only around a quarter of this area is protected.

Deforestation rates are high in this region, with forest fires also posing a significant threat. Added to this, the Brazilian Government’s ongoing development programme includes several new hydroelectricity dams and an extension of the road system planned within the Amazon.

“It goes without saying that we are really excited about this new discovery”, said researcher Felipe Ennes Silva, who collected the data for the new species description. “It is always thrilling to find something new in the Amazon, as it reminds us just how special this rainforest is and how lucky we are to have it on our doorstep.

“But it will take more than luck if we are to keep making scientific finds like this. The rainforest is under threat like never before, and it will take dedicated, hard work – not just by conservationists but by the government and every other sector of society too – to make sure that this forest ecosystem can continue to support a wide diversity of life and help regulate our planet’s climate.”

The Conservation Leadership Programme (CLP) is a partnership between BirdLife InternationalFauna & Flora International and the Wildlife Conservation Society that promotes the professional development of conservation leaders. Through training and mentoring, funding, and the provision of networking opportunities, the CLP ensures that these emerging leaders have the skills and knowledge required to address today’s most pressing conservation issues.

Giant lemur fossils discovery in Madagascar


This video says about itself:

Enormous Underwater Fossil Graveyard Found

8 January 2015

National Science Foundation-funded anthropologists and paleontologists uncovered what could be the largest single collection of lemur remains ever found. What’s more, they found it in a most unusual place–hidden in a series of underwater caves in a remote desert region of Madagascar.

Described as a lemur graveyard, the discovery of hundreds of potentially thousand-year old skeletons make it one of the most unique sites in the world. The finding, reported in this video, could be important for understanding human relatives and other animals and result in a totally new era for underwater paleontology.

From the Washington Post in the USA:

In an underwater graveyard, scientists discover bones of giants from Madagascar’s past

By Sarah Kaplan

February 19 2015

Not too long ago, huge animals dominated the island of Madagascar: elephant birds the height of professional basketball players, giant, lumbering tortoises, massive lemurs that weighed up to 15 times as much as their smaller, living relatives.

Those creatures have all but died out within the past thousand years in one of the swiftest extinction events known to scientists. Researchers still puzzle over what exactly led to their demise. But a newly-discovered “underwater graveyard” filled with thousands of fossils may offer a key to understanding what happened to Madagascar’s megafauna.

A team led by National Geographic fellow and Brooklyn College professor Alfred Rosenberger found three flooded caves in Tsimanampesotse National Park, each containing an unprecedented number of large, perfectly preserved specimens. One in particular, Aven Cave, is so packed with bones that divers felt them every time they put their hands down.

“It’s just phenomenal,” researcher Laurie Godfrey, a paleontologist at the University of Massachusetts at Amherst, said in a phone interview with The Washington Post. “A huge cache of fossils like this has never been explored before. Now that we know that it’s there, it’s opening up a new era in paleontological exploration.”

The researchers’ most prized findings are the bones of several extinct species of giant lemurs, ranging from several hundred to several thousands of years old. Among them are specimens of Megaladapis, a big-nosed, beady-eyed creature whose heavy, squat body more closely resembled a koala’s than those of the diminutive lemurs we know today, and Archaeoindris, the largest known lemur species that was the same size and weight as a gorilla.

The discovery, which National Geographic announced Tuesday, is just the first step in what Godfrey hopes will be a more thorough investigation of the caves. The initial sweep brought up so many fossils that researchers haven’t even begun to dig into the sediments on the cave floors. Once they do, Godfrey estimates they’ll find thousands of specimens from dozens of extinct species.

The caves remained unexplored for so long because of the difficulty of probing their flooded interiors. In Aven Cave, where the fossils were most abundant, the water is 130 feet deep and often murky.

But that same water is also what makes the caves such perfect places to find fossils.

“In a flooded cave the preservation can be just marvelous,” Godfrey said. “Nothing’s bothering them, nothing’s disturbing them.”

The quality of the fossils will be key for scientists’ research into the causes of the animals’ disappearance. Godfrey said that researchers will likely be able to obtain DNA samples from the specimens, carbon date them to see when they died, and examine them for cut marks or other signs of human butchering.

“All of this information can help us flesh out the story that we’re telling about what happened to the giant lemurs and the associated fauna,” she said.

It’s long been understood that human arrival on Madagascar about 2,000 years ago coincided with the sudden die-off of much of the island’s wildlife. Two-thirds of the species that lived on the island a millennium ago are now extinct, in part because of changes caused by humans, Godfrey said. What’s not clear is exactly how those changes led to the animals’ demise.

“You’re dealing with a situation where not only are humans coming but they’re bringing a lot of other animals and plants that transform the habitat. They’re hunting,” for example, she said, and “it could be that certain species didn’t want to come near water or food sources because humans were around. There’s competition with new introduced species. There’s a number of long, complicated stories people have put forth as to why these animals are extinct.”

Untangling those stories isn’t just a matter of understanding history — it can help with conservation efforts today. Lemurs are the most threatened mammal species on Earth, according to a policy paper published last year in the journal Science, and Madagascar is the only place where they are found in the wild.

“It’s a very sad situation in Madagascar. The threat to species is tremendous, there’s a high rate of extinction,” Rosenberger said in a video for National Geographic. “We’d like to know what the interaction was between people, climate change, habitat change … that contributed to the demise of the giant lemurs. Because knowing that might give us some perspective on what we have to prepare for the future.”

Indonesian silvery gibbons’ love story


This video from Java, Indonesia says about itself:

When Two Silvery Gibbons Meet, It’s Love at First Touch | Conservation International (CI)

13 February 2015

Since gibbons can only survive in the wild as bonded pairs, rehabilitation efforts at the Java Gibbon Center depend on successful matchmaking. Supported by Conservation International and located on the edge of Indonesia’s Gunung Gede Pangrango National Park, the center brought together two rescued gibbons, Jowo (male) and Bombom (female) — creating one of nature’s cutest love stories.
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To learn more about this gibbon love story and Conservation International’s work to protect their habitiat, see here.

After the story of the two Peruvian spider monkeys

Purgatorius, world’s oldest primate?


This video says about itself:

PurgatoriusExtinction of the Dinosaurs

29 November 2014

Purgatorius and the extinction of the dinosaurs.

Scenes from Animal Planet‘s Animal Armageddon.

From Proceedings of the National Academy of Sciences of the United States of America:

Oldest known euarchontan tarsals and affinities of Paleocene Purgatorius to Primates

Significance

Purgatorius has been considered a plausible ancestor for primates since it was discovered, but this fossil mammal has been known only from teeth and jaw fragments. We attribute to Purgatorius the first (to our knowledge) nondental remains (ankle bones) which were discovered in the same ∼65-million-year-old deposits as dentitions of this putative primate. This attribution is based mainly on size and unique anatomical specializations known among living euarchontan mammals (primates, treeshrews, colugos) and fossil plesiadapiforms.

Results of phylogenetic analyses that incorporate new data from these fossils support Purgatorius as the geologically oldest known primate. These recently discovered tarsals have specialized features for mobility and provide the oldest fossil evidence that suggests arboreality played a key role in earliest primate evolution.

Abstract

Earliest Paleocene Purgatorius often is regarded as the geologically oldest primate, but it has been known only from fossilized dentitions since it was first described half a century ago. The dentition of Purgatorius is more primitive than those of all known living and fossil primates, leading some researchers to suggest that it lies near the ancestry of all other primates; however, others have questioned its affinities to primates or even to placental mammals.

Here we report the first (to our knowledge) nondental remains (tarsal bones) attributed to Purgatorius from the same earliest Paleocene deposits that have yielded numerous fossil dentitions of this poorly known mammal. Three independent phylogenetic analyses that incorporate new data from these fossils support primate affinities of Purgatorius among euarchontan mammals (primates, treeshrews, and colugos).

Astragali and calcanei attributed to Purgatorius indicate a mobile ankle typical of arboreal euarchontan mammals generally and of Paleocene and Eocene plesiadapiforms specifically and provide the earliest fossil evidence of arboreality in primates and other euarchontan mammals. Postcranial specializations for arboreality in the earliest primates likely played a key role in the evolutionary success of this mammalian radiation in the Paleocene.

Rhesus monkeys recognize themselves in mirrors


This video says about itself:

Monkeys May Be Able To Recognize Themselves In A Mirror With Training

8 January 2015

Researchers at the Chinese Academy of Sciences may have taught rhesus monkeys to recognize themselves in a mirror for the first time.

The team trained the monkeys to pass the “mark test”, considered to be the primary method of determining self-recognition.

For several weeks, training involved shining a laser light on seven monkeys in front of a mirror.

At the end of this period, they could touch the virtual mark by seeing it on a mirror image of themselves which was considered a passing of the mark test.

The monkeys also displayed self-directed behavior in the mirror to examine parts they couldn’t normally see like their mouths and genitals.

Previously, elephants, pigeons, dolphins, and apes were among the other animals which passed the test for self-recognition but not monkeys.

The monkeys that successfully passed the test retained the ability for one year.

However, they could not pass on the skill to their untrained peers.

Those that did not get trained by researchers failed to self-recognize.

Self-recognition is considered an important indicator of the brain’s capacity to empathize with others.

Despite the study’s success, Gordon Gallup Jr., developer of the mark test, blasts the results as “fundamentally flawed,” since they focus on training and do not prove an inherent understanding of behavior.

From Current Biology:

Mirror-Induced Self-Directed Behaviors in Rhesus Monkeys after Visual-Somatosensory Training

Liangtang Chang, Qin Fang, Shikun Zhang, Mu-ming Poo, Neng Gong

Highlights

•We developed a novel training strategy to study mirror self-recognition in monkeys
•Trained rhesus monkeys passed the conventional mark test in front of a mirror
•Trained rhesus monkeys exhibited spontaneous mirror-induced self-directed behaviors
•Rhesus monkeys may be useful for studying the origin of mirror self-recognition

Summary

Mirror self-recognition is a hallmark of higher intelligence in humans. Most children recognize themselves in the mirror by 2 years of age [ 1 ]. In contrast to human[s] and some great apes, monkeys have consistently failed the standard mark test for mirror self-recognition in all previous studies [ 2–10 ]. Here, we show that rhesus monkeys could acquire mirror-induced self-directed behaviors resembling mirror self-recognition following training with visual-somatosensory association. Monkeys were trained on a monkey chair in front of a mirror to touch a light spot on their faces produced by a laser light that elicited an irritant sensation.

After 2–5 weeks of training, monkeys had learned to touch a face area marked by a non-irritant light spot or odorless dye in front of a mirror and by a virtual face mark on the mirroring video image on a video screen. Furthermore, in the home cage, five out of seven trained monkeys showed typical mirror-induced self-directed behaviors, such as touching the mark on the face or ear and then looking at and/or smelling their fingers, as well as spontaneously using the mirror to explore normally unseen body parts. Four control monkeys of a similar age that went through mirror habituation but had no training of visual-somatosensory association did not pass any mark tests and did not exhibit mirror-induced self-directed behaviors.

These results shed light on the origin of mirror self-recognition and suggest a new approach to studying its neural mechanism.

Indonesian monkeys and trees, new study


This video is called Long Nosed Monkey : Documentary on Borneo‘s Proboscis Monkey.

By Leigh Cooper, special to mongabay.com:

Monkey sleep, monkey do: how primates choose their trees

December 31, 2014

Primates don’t monkey around when deciding where to spend the night, but primatologists have had a poor grasp on what drives certain monkeys toward specific trees. Now, two extensive studies of Indonesian primates suggest that factors in selecting trees each evening are site-specific and different for each species—and that some overnight spots result in conflicts between monkeys and humans.

“We have to understand what monkeys need [in order] to sleep to know what we have to protect,” said primate scientist Fany Brotcorne of the University of Liège in Belgium, leader of one of the research teams, in an interview with mongabay.com.

When monkeys choose their evening perch, they weigh more than just comfort. The main factors scientists suspect are safety from predators, distance to feeding grounds, human interactions, insect avoidance, and competition with other primates.

“Primates may be spending up to 12 hours at their sleeping sites, and yet we really don’t know much about them,” said Adrian Barnett of the University of Roehampton, in London, U.K., a primatologist not involved in the new work, in an email to mongabay.com.

The two unaffiliated studies occurred on neighboring Indonesian islands. Brotcorne’s team spent 56 nights in the Bali Barat National Park in Bali studying long-tailed macaques (Macaca fascicularis), a thriving primate species. In West Kalimantan on the island of Borneo, primatologist Katie Feilen of the University of California at Davis followed the sleeping behaviors of endangered proboscis monkeys (Nasalis larvatus) for 132 nights.

Both groups noted the sizes and shapes of trees favored by the monkeys. Brotcorne’s group also measured the distance between sleeping sites and human outposts such as temples, tourist areas, or roads.

The proboscis monkeys returned each night to tall, isolated trees near rivers. The monkeys gather in trees that jut above the canopy to avoid predators and insects, believes Feilen. Predators can’t crawl from tree to tree toward the monkeys if the trees’ branches don’t touch. At the same time, the monkeys’ lofty—and windy—perches help them avoid malaria-ridden mosquitoes that tend to remain within the canopy.

“I think insect and disease ecology plays a bigger role in all these questions of primatology than we are all thinking,” said Feilen.

The long-tailed macaques snoozed away in trees near human-modified areas. Brotcorne suspects food availability was the main factor driving the macaques’ bunk choice. The monkeys scooted closer to a Hindu temple and tourist area where fruit, rice, and crackers abounded during the peak tourist season. The timing of their move also coincided with the start of the dry season and a decline in natural fruit production. The two teams reported their findings side-by-side this month in the American Journal of Primatology.

There is not just one evolutionary force influencing sleeping tree preference for primates, pointed out both lead authors.

“Both papers are significant in that they are showing the importance of sleeping sites in primate ecology,” said Barnett. “What is needed is a collation of data that is sufficiently broad to allow general theories to be put up [about sleeping tree selection].”

The distinct sleeping site chosen by the two species also influences the primates’ interactions with humans. Loggers preferentially remove the tall riverside trees favored by the endangered proboscis monkeys, threatening the species’ habitat, said Feilen. The proboscis monkeys she studied had to contend with deforestation by mining and palm oil companies. Also, local hunters knew where to find the predictable primates.

On the other hand, macaques and humans have competed for space and food in human-modified areas for centuries. But their close contact worries Brotcorne because diseases can cross from monkeys to humans and vice versa. Human food is not the healthiest diet for monkeys, she added.

“If you go to the tourist monkey forests, you will see obese monkeys,” said Brotcorne.

Citations:

Feilen, K., and A. Marshall. 2014. Sleeping site selection by proboscis monkeys (Nasalis larvatus) in West Kalimantan, Indonesia. American Journal of Primatology 76: 1127-1139.
Brotcorne, F., C. Maslarov, N. Wandia, A. Fuentes, R. Beudels-Jamar, and M. Huynen. 2014. The role of anthropic, ecological, and social factors in sleeping site choice by long-tailed Macaques (Macaca fascicularis). American Journal of Primatology 76: 1140-1150.

Leigh Cooper is a graduate student in the Science Communication Program at the University of California, Santa Cruz.