Category: Environment

{Chimps perform grooming behavior the same way their mothers did.}

Think of all the things your mom taught you — sit up straight, close your mouth when you chew your food, remember to say please and thank you…the list goes on.

When it comes to learning how to behave, though, humans aren’t alone in looking to our Moms.

Led by Richard Wrangham, Ruth Moore Professor of Biological Anthropology, a group of researchers has shown, for the first time, that chimpanzees learn certain grooming styles from their mothers. Once learned, chimps continued to perform the behavior the same way, long after the death of their mothers. The study is described in a November 21 paper in Current Biology.

“I think what it really shows is how strong the maternal influence is,” Wrangham said. “It’s very charming, really — our oldest known son was almost 40 years old, still doing what his long-dead mother did.”

Known as “high-arm grooming,” the behavior occurs during the regular grooming sessions chimps engage in throughout the day. As two chimps groom each other, each raise one arm and either clasp hands or cross their arms as they continue to groom. Though brief — sessions average only about 45 seconds — chimps have been observed in the behavior as many as ten times a day.

But while grooming behavior is universal among chimps, high-arm grooming is not.

The behavior has been observed in eight chimp populations across Africa, Wrangham said, each of which show differing rates of clasping and non-clasping, but is notably absent in three other well-studied populations.

It’s not clear, however, whether any significance should be attached to those differences — at present, researchers have no clear answer as to why chimps engage in high-arm grooming, or what benefits they get from it.

“So what we wanted to understand was what’s responsible for the variation in palm-to-palm clasping,” Wrangham said. “When a young female joins a new group does she look at what everyone else is doing…and then do what the rest of the group does for the rest of her life?”

To find out, Wrangham and colleagues collected the most detailed data ever on how — and how often — chimps in a particular population engaged in high-arm grooming, and they quickly realized that nearly all previous theories about the behavior were wrong.

“This type of behavior, which seems so trivial in many ways — whether you clasp hands or cross arms — has been suggested as signaling membership in a group,” Wrangham said. “People often see these types of strange behaviors we see in chimps and wonder if it is some sort of group identification sign.”

“Alternatively, people have suggested that maybe it signals a special type of social relationship if two individuals do it more often with one another. But what we’re showing with this paper is that none of the obvious possibilities figure out,” Wrangham said. “The pattern varies widely within the group, it’s not closely associated with friendship, it doesn’t vary by age or sex, and it does not depend on how long an individual has been in the community.”

In fact, he said, the only connection researchers were able to identify was the maternal one. The chimpanzees are copying their mothers, not identifying with the larger community.

Like human children, young chimps learn many behaviors from their mothers, from which foods to eat to how to use tools, and — among mothers who engage in it — how to perform high-arm grooming. And since young chimps may groom almost exclusively with their mothers until about age 12, Wrangham said it’s hardly any wonder that the grooming style stays with them into adulthood.

“Even when they’re adults, even after their mothers are long dead, they still do it the same way their mother did it.” Wrangham said. “This is the first time anyone has realized this, and the pattern is delightfully clear.”

While it’s tempting to assign some larger significance to the behavior, Wrangham said studies this far haven’t been able to show whether high-arm grooming carries any social meaning.

“People may say it’s important because they stick to it,” he said. “But the alternative view is that no one in the group cares. There’s never rejection (when a clasper meets a non-clasper) — everyone has tended to think that this is something that would be seen more among individuals that have a strong alliance relationship, but it turns out to not be true.”

That finding, Wrangham said, leaves several questions still to be answered, and the hope is that further study may yet yield some insights into the behavior.

“Now that we know some families clasp hands as much as 90 percent of the time, and others do it only 10 percent, what happens when you get two individuals high-arm grooming together when one is a clasper and the other is not?” Wrangham said. “What is it that decides which pattern they will use? Is it dominance? Is it the higher ranking individual? The older one? Or maybe it is the one that initiates?

“Our current evidence suggests that neither dominance nor age carries sway. Eventually I hope we can work out the social significance of this quirky behavior. If we can find a pattern for which individual “wins” when a clasper grooms with a non-clasper, maybe we will get a clue to why individuals do high-arm grooming at all.”

{How plants use a light receptor as a thermosensor.}

Plants respond very sensitive to temperature changes in their environment. At 22 degrees Celsius, for example, the model plant Arabidopsis shows compact growth. But if the temperature rises only a few degrees, plants exhibit an increased elongation growth in the shoot and leaves, enabling plant organs to cool down more easily by evaporation. How plants sense temperature was unknown, until now. In two complementary studies published in Science magazine, researchers from the University of Freiburg collaborated with researchers from Cambridge, England; Buenos Aires, Argentina; and St. Louis, Missouri, USA, to demonstrate how the light receptor phytochrome B also works as a temperature sensor in plants.

Phytochromes are photoreceptor proteins that control a number of physiological processes in higher plants, including seed germination, seedling development, induction of flowering and the shade avoidance. The spectral composition of a plant’s light environment changes according to where the plant is growing: The proportion of red light is high in the direct sunlight, while in the shade of vegetation, blue and red light is filtered out, and far red becomes enriched. Phytochromes can absorb light and act as light driven molecular switches. While the red light portion in sunlight activates phytochromes, far red light inactivates them. Based on this, plants are able to determine the amount of red light in their light environment. Active phytochrome B inhibits elongation growth and promotes compact plant growth instead. It binds to regulatory sequences, or promoters, of certain genes involved for example in the regulation of elongation growth, thus controlling their activity.

It has been known for some time that phytochromes can change from the active to the inactive state, regardless of light conditions. This process is known as dark reversion. The plant physiologists from the University of Freiburg demonstrated previously that the inactivation of phytochrome B via dark reversion can occur in reactions with two different speeds. A slower dark reversion mechanism ensures that the amount of active phytochrome B gradually declines during the night. A second, about 100 times faster reversion process competes with the light activation of phytochrome B and thus allows the plant to measure the intensity of light during the day. Besides, the researchers discovered that the speed of these two inactivation processes depends strongly on temperature.

Using a special spectroscopy method that allows measuring the amount of active phytochrome B in living seedlings, the scientists demonstrated how much temperature affects the two dark reversion rates. The temperature dependency of the slower dark reversion reaction determines how long phytochrome B remains active during the night and can therefore bind to the gene promoters. At higher temperatures, phytochrome B is inactivated more rapidly and is released from promoters faster than at lower temperatures. Temperature also influences the activity of phytochrome B during the day. At higher temperatures, the researchers detected reduced levels of the photoreceptors’ active form already in the light phase that was caused by the temperature-dependency of the fast dark reversion mechanism. Rising temperatures inactivate phytochrome B, particularly in weak light, which in turn promotes elongation growth. Using these mechanisms, plants are able to adapt their development to changes in their environment.

The researchers involved in the studies are Dr. Cornelia Klose, Prof. Dr. Andreas Hiltbrunner, and Prof. Dr. Eberhard Schäfer from the Department of Molecular Plant Physiology of the Institute of Biology II at the University of Freiburg. Hitbrunner and Schäfer are members of the BIOSS Centre for Biological Signalling Studies cluster of excellence, also at the University of Freiburg.

{In November, the Paris Climate Agreement goes into effect to reduce global carbon emissions. To achieve the set targets, experts say capturing and storing carbon must be part of the solution. Several projects throughout the world are trying to make that happen. Now, a study on one of those endeavors, reported in the ACS journal Environmental Science & Technology Letters, has found that within two years, carbon dioxide (CO2) injected into basalt transformed into solid rock.}

Lab studies on basalt have shown that the rock, which formed from lava millions of years ago and is found throughout the world, can rapidly convert CO2 into stable carbonate minerals. This evidence suggests that if CO2 could be locked into this solid form, it would be stowed away for good, unable to escape into the atmosphere. But what happens in the lab doesn’t always reflect what happens in the field. One field project in Iceland injected CO2 pre-dissolved in water into a basalt formation, where it was successfully stored. And starting in 2009, researchers with Pacific Northwest National Laboratory and the Montana-based Big Sky Carbon Sequestration Partnership undertook a pilot project in eastern Washington to inject 1,000 tons of pressurized liquid CO2 into a basalt formation.

After drilling a well in the Columbia River Basalt formation and testing its properties, the team injected CO2 into it in 2013. Core samples were extracted from the well two years later, and Pete McGrail and colleagues confirmed that the CO2 had indeed converted into the carbonate mineral ankerite, as the lab experiments had predicted. And because basalts are widely found in North America and throughout the world, the researchers suggest that the formations could help permanently sequester carbon on a large scale.

The authors acknowledge funding from the U.S. Department of Energy; the National Energy Technology Laboratory; the Big Sky Carbon Sequestration Partnership; Shell Exploration & Production Company; Portland General Electric; and Schlumberger Inc.

{Way before trees or lichens evolved, soils on Earth were alive, as revealed by a close examination of microfossils in the desert of northwestern Australia, reports a team of University of Oregon researchers.
}
These tiny fossils require a microscope to see and probably represent whole organisms. The 3,000 million-year-old Australian rocks have long been thought to be of marine origin. However, “a closer look at the dusty salt minerals of the rocks suggests they had to have experienced evaporation on land,” said UO paleontologist Gregory Retallack, lead author on a study in the December issue of the international journal Gondwana Research.

Other mineral and chemical tracers found in the rocks also required weathering in soils of the distant geological past, he said.

“Life was not only present but thriving in soils of the early Earth about two thirds of the way back to its formation from the solar nebula,” Retallack said. The origin of the solar system — and Earth — occurred some 4.6 billion years ago.

The study outlines a microbiome of at least five different kinds of microfossils recognized from their size, shape and isotopic compositions. The largest and most distinctive microfossils are spindle-shaped hollow structures of mold-like actinobacteria, still a mainly terrestrial group of decomposers that are responsible for the characteristic earthy smell of garden soil.

Other sphere-shaped fossils are similar to purple sulfur bacteria, which photosynthesize organic compounds in the absence of oxygen while leaving abundant sulfate minerals in the soil.

“With cell densities of over 1,000 per square millimeter and a diversity of producers and consumers, these microfossils represent a functioning terrestrial ecosystem, not just a few stray cells,” said Retallack, a professor in the Department of Earth Sciences and director of paleontology collections at the Museum of Natural and Cultural History. “They are evidence that life in soils was critical to the cycles of carbon, phosphorus, sulfur and nitrogen very early in the history of the planet.”

The new discoveries by the UO team are potentially controversial because many scientists have long pointed to stromatolites, a life form that emerged 3.7 billion years ago, and other marine life as evidence of life that evolved in the sea and found their way into intertidal rock formations.

Retallack referred to the memoir “Lab Girl” published this year by Hope Jahren, a geobiologist at the University of Hawaii, who wrote: “For several billion years, the whole of the Earth’s land surface was completely barren. Even after life had richly populated the oceans, there is no clear evidence for any life on land.”

“The newly recognized microfossils may have supplied some evidence at last,” Retallack said.

The ancient soils with sulfate salts and microfossils come from the Pilbara region of Western Australia. They are superficially similar to those found recently by the Mars rover Curiosity. “They may,” he said, “be useful as guides for the discovery of life on other planets.”

Critical to the new discoveries were advanced imaging and analyses performed with the cluster of instruments in the Center for Advanced Materials Characterization of Oregon, commonly known as CAMCOR, at the UO.

{Scientists have discovered a new large valley on Mercury that may be the first evidence of buckling of the planet’s outer silicate shell in response to global contraction. The researchers discovered the valley using a new high-resolution topographic map of part of Mercury’s southern hemisphere created by stereo images from NASA’s MESSENGER spacecraft. The findings were reported in a new study published in Geophysical Research Letters, a journal of the American Geophysical Union.}

The most likely explanation for Mercury’s Great Valley is buckling of the planet’s lithosphere — its crust and upper mantle — in response to global contraction, according to the study’s authors. Earth’s lithosphere is broken up into many tectonic plates, but Mercury’s lithosphere consists of just one plate. Cooling of Mercury’s interior caused the planet’s single plate to contract and bend. Where contractional forces are greatest, crustal rocks are thrust upward while an emerging valley floor sags downward.

“There are examples of lithospheric buckling on Earth involving both oceanic and continental plates, but this may be the first evidence of lithospheric buckling on Mercury,” said Thomas R. Watters, senior scientist at the Center for Earth and Planetary Studies at the Smithsonian’s National Air and Space Museum in Washington, D.C., and lead author of the new study.

The valley is about 400 kilometers (250 miles) wide with its floor as much as 3 kilometers (2 miles) below the surrounding terrain. The valley is more than 1,000 kilometers (600 miles) long and extends into the Rembrandt basin, one of the largest and youngest impact basins on Mercury.

The valley is bound by two large fault scarps — steps on the planet’s surface where one side of a fault has moved vertically with respect to the other. Mercury’s contraction caused the fault scarps bounding the Great Valley to become so large they essentially became cliffs. The elevation of the valley floor is far below the terrain surrounding the mountainous faults scarps, which suggests the valley floor was lowered by the same mechanism that formed the scarps themselves, according to the study authors.

“Unlike Earth’s Great Rift Valley in East Africa, Mercury’s Great Valley is not caused by the pulling apart of lithospheric plates due to plate tectonics; it is the result of the global contraction of a shrinking one-plate planet,” Watters said. “Even though you might expect lithospheric buckling on a one-plate planet that is contracting, it is still a surprise when you find that it’s formed a great valley that includes the largest fault scarp and one of the largest impact basins on Mercury.”

{It is very likely that 2016 will be the hottest year on record, with global temperatures even higher than the record-breaking temperatures in 2015. Preliminary data shows that 2016’s global temperatures are approximately 1.2° Celsius above pre-industrial levels, according to an assessment by the World Meteorological Organization (WMO).}

Global temperatures for January to September 2016 have been about 0.88° Celsius (1.58°F) above the average (14°C) for the 1961-1990 reference period, which is used by WMO as a baseline. Temperatures spiked in the early months of the year because of the powerful El Niño event of 2015-16. Preliminary data for October indicate that they are at a sufficiently high level for 2016 to remain on track for the title of hottest year on record. This would mean that 16 of the 17 hottest years on record have been this century (1998 was the other one).

Long-term climate change indicators are also record breaking. Concentrations of major greenhouse gases in the atmosphere continue to increase to new records. Arctic sea ice remained at very low levels, especially during early 2016 and the October re-freezing period, and there was significant and very early melting of the Greenland ice sheet.

Ocean heat was boosted by the El Niño event, contributing to coral reef bleaching, and above-average sea-level rise.

The deadliest event so far in 2016 has been Hurricane Matthew, which was Haiti’s worst humanitarian emergency since the 2010 earthquake. Throughout the year, extreme weather led to considerable socio-economic losses in all regions of the world.

“Another year. Another record. The high temperatures we saw in 2015 are set to be beaten in 2016,” said WMO Secretary-General Petteri Taalas. The extra heat from the powerful El Niño event has disappeared. The heat from global warming will continue,” he said.

“In parts of Arctic Russia, temperatures were 6°C to 7°C above the long-term average. Many other Arctic and sub-Arctic regions in Russia, Alaska and northwest Canada were at least 3°C above average. We are used to measuring temperature records in fractions of a degree, and so this is different,” said Mr Taalas.

“Because of climate change, the occurrence and impact of extreme events has risen. ‘Once in a generation’ heatwaves and flooding are becoming more regular. Sea level rise has increased exposure to storm surges associated with tropical cyclones,” he said.

“The Paris Agreement came into force in record time and with record global commitment. The World Meteorological Organization will support the translation of the Paris Agreement into action,” he said.

“WMO is working to improve monitoring of greenhouse gas emissions to help countries reduce them. Better climate predictions over timescales of weeks to decades will help key sectors like agriculture, water management, health and energy plan for and adapt to the future. More impact-based weather forecasts and early warning systems will save lives both now and in the years ahead. There is a great need to strengthen the disaster early warning and climate service capabilities of especially developing countries. This is a powerful way to adapt to climate change,” said Mr Taalas.

WMO published the provisional statement for 2016 to inform the United Nations Climate Change conference taking place in Marrakech, Morocco (COP22). The final statement will be released in early 2017. For the first time, the assessment includes input from UN partners on the humanitarian impact.

It complements a report on the 2011-2015 global climate, which was also submitted to COP22 to give a longer-term picture of the climate and to address multi-year events like droughts. That report showed that, of 79 studies published by the Bulletin of the American Meteorological Society between 2011 and 2014, more than half found that human-induced climate change contributed to the extreme event in question. Some studies found that the probability of extreme heat increased by 10 times or more.

Highlights:

Temperatures

Global temperatures for January to September 2016 were approximately 1.2°C above pre-industrial levels and 0.88°C (1.58°F) above the average for the 1961-1990 reference period. They were especially warm in the early months of the year, with record monthly anomalies of +1.12°C (+2.02°F) in February and +1.09°C (+1.96°F) in March. Operational October data from the European Centre for Medium Range Weather Forecasting ERA-40 reanalysis indicate that October temperature anomalies were similar to May to September ones.

Temperatures were above the 1961-90 average over the vast majority of land areas. In parts of Arctic Russia around the Ob River estuary and Novaya Zemlya, they were 6°C to 7°C above average. Many other Arctic and sub-Arctic regions in Russia, Alaska and northwest Canada were at least 3°C above average. More than 90% of Northern Hemisphere land areas outside the tropics were at least 1°C above average. Temperatures were less extreme in the Southern Hemisphere, but many areas were still 1°C or more above average, including northern South America, northern and eastern Australia, and much of southern Africa.

The only large land area with below-average temperatures was part of subtropical South America (northern and central Argentina, parts of Paraguay and lowland Bolivia).

Oceans

Temperatures were above normal over most ocean areas. This contributed to significant coral bleaching and disruption of marine ecosystems in some tropical waters, including the Great Barrier Reef off the east coast of Australia, and Pacific island countries such as Fiji and Kiribati. Coral mortality of up to 50% was reported in parts of the Great Barrier Reef.

The most prominent area of below-normal sea surface temperatures was the Southern Ocean south of 45° South (especially around the Drake Passage between South America and Antarctica, where temperatures were more than 1°C below normal in places).

Global sea levels rose about 15 millimetres between November 2014 and February 2016 as a result of El Niño, well above the post-1993 trend of 3 to 3.5 mm per year, with the early 2016 values reaching new record highs. Since February, sea levels have remained fairly stable.

Greenhouse gas concentrations

Annual average global carbon dioxide concentrations in 2015 reached 400 parts per million (ppm) for the first time. Initial observations indicate new records in 2016. At Cape Grim (Australia), CO2 levels in August averaged 401.42 ppm, compared with 398.13 ppm in August 2015. At Mauna Loa (Hawaii), mean weekly concentrations of CO2 as of 23 October were 402.07 ppm, compared with 398.50 ppm at the same time in 2015, whilst the May 2016 value of 407.7 ppm was the highest monthly value on record.

Ice and snow cover

Arctic sea ice extent was well below normal throughout the year. The seasonal minimum in September was 4.14 million square kilometres, the equal-second (with 2007) lowest extent on record after 2012. The winter maximum in March was the lowest on record. The autumn freeze-up has also been much slower than normal; the sea ice extent as of the end of October is the lowest on record for the time of year.

After several years of well-above-normal values, Antarctic sea ice extent fell to near normal by the start of 2016. It reached a seasonal maximum nearly a month earlier than usual. It was still well below normal as of the end of October.

Summer melting on the Greenland ice sheet was substantially above the 1990-2013 average, with especially strong melting in July, but was less than in the record melting year of 2012.

High-Impact events

Numerous weather events had major impacts in 2016. The most significant, in terms of casualties, was Hurricane Matthew in October. According to Haitian government figures at the start of November, there were 546 confirmed deaths and 438 injured as a result of the hurricane. After crossing Haiti, Matthew tracked north and went on to cause damage in Cuba and the Bahamas, before tracking along the east coast of the United States and making landfall in South Carolina, causing major flooding.

Typhoon Lionrock caused destructive flooding and heavy casualties in the Democratic People’s Republic of Korea, and Cyclone Winston was the most severe tropical on record to affect Fiji. In total, there have been 78 tropical cyclones globally in 2016 as of 31 October, close to the long-term average.

The Yangtze basin in China had its most significant summer floods since 1999, killing 310 people and causing an estimated US$14 billion in damage. Flooding and landslides in Sri Lanka in mid-May left more than 200 people dead or missing, and displaced several hundred thousand. Above-normal seasonal rainfall in the Sahel led to significant flooding in the Niger River basin, with the river reaching its highest levels in about 50 years in Mali.

There were a number of major heatwaves during 2016. The year started with an extreme heatwave in southern Africa, exacerbated by the ongoing drought. Many stations set all-time records, including 42.7°C at Pretoria and 38.9°C at Johannesburg on 7 January. Thailand saw a national record of 44.6°C on 28 April. Phalodi saw a new record for India of 51.0°C on 19 May. Record or near-record temperatures occurred in parts of the Middle East and north Africa on a number of occasions in summer. Mitribah (Kuwait) recorded 54.0°C on July 21 which, subject to ratification through standard WMO procedures, will be the highest temperature on record for Asia. The following day, 53.9°C was recorded at Basra (Iraq) and 53.0°C at Delhoran (Iran).

The most damaging wildfire in Canadian history occurred in May in the city of Fort McMurray in Alberta. The fire ultimately burned an area of about 590,000 hectares and was Canada’s most costly natural disaster. It led to the total evacuation of the city and ultimately destroyed 2,400 buildings, causing 4 billion Canadian dollars (US$3 billion) in insured losses and several billion more in other losses.

Major droughts affected several parts of the world, most of them associated with the El Niño event, which had a big influence on precipitation. Southern Africa experienced a second consecutive bad rainy season in 2015-16. Most of the region normally receives little rain between May and October, and the World Food Programme estimates that 17 million people will require assistance during the “lean season” ahead of the next harvest in early 2017.

Humanitarian consequences

Annual and long-term changes in the climate system can aggravate social, humanitarian and environmental pressure. According to International Organisation for Migration, population migration is expected to increase as a result of more frequent and potentially more intense weather-related disasters, competition and conflict over shrinking resources, and rising sea levels rendering coastal and low lying zones uninhabitable.

According to United Nations High Commissioner for Refugees), in 2015 there were 19.2 million new displacements associated with weather, water, climate and geophysical hazards in 113 countries, more than twice as many as for conflict and violence. Of these, weather-related hazards triggered 14.7 million displacements. South and East Asia dominated in terms of the highest absolute figures, but no region of the world was unaffected. Equivalent data for 2016 are not yet available.

Extreme weather and climate related events influenced by the strong El-Niño in 2015/2016 had significant negative impacts on agriculture and food security. More than 60 million people around the world were affected by these events, according to the Food and Agriculture Organization.

{The lack of liquid water on the surface of Mars today has been demonstrated by new evidence in the form of meteorites on the Red Planet examined by an international team of planetary scientists.}

In a study led by the University of Stirling, an international team of researchers has found the lack of rust on the meteorites indicates that Mars is incredibly dry, and has been that way for millions of years.

The discovery, published in Nature Communications, provides vital insight into the planet’s current environment and shows how difficult it would be for life to exist on Mars today.

Mars is a primary target in the search for life outside Earth, and liquid water is the most important pre-requisite for life.

Dr Christian Schröder, Lecturer in Environmental Science and Planetary Exploration at the University of Stirling and Science Team Collaborator for the Mars Exploration Rover Opportunity mission, said:

“Evidence shows that more than 3 billion years ago Mars was wet and habitable. However, this latest research reaffirms just how dry the environment is today. For life to exist in the areas we investigated, it would need to find pockets far beneath the surface, located away from the dryness and radiation present on the ground.”

A study published last year, which used data from the Curiosity Rover investigating Gale crater on Mars, suggested that very salty liquid water might be able to condense in the top layers of Martian soil overnight.

“But, as our data show, this moisture is much less than the moisture present even in the driest places on Earth,” explains Dr Schröder.

Using data from the Mars Exploration Rover Opportunity, the scientists examined a cluster of meteorites at Meridiani Planum — a plain just south of the planet’s equator and at a similar latitude to Gale crater.

Dr Schröder and his team have for the first time calculated a chemical weathering rate for Mars, in this case how long it takes for rust to form from the metallic iron present in meteorites.

This chemical weathering process depends on the presence of water. It takes at least 10 and possibly up to 10,000 times longer on Mars to reach the same levels of rust formation than in the driest deserts on Earth and points to the present-day extreme aridity that has persisted on Mars for millions of years.

{New research suggests that male chimpanzees are more invested in protecting their own offspring than previously thought. Researchers found male chimpanzees spend time with non-mating female chimpanzees that are caring for their offspring. This finding is unexpected since the species is highly promiscuous and researchers previously questioned whether male chimpanzees could recognize their offspring.}

Because males spending time with nursing mothers did not increase the likelihood that they would be the father of that mother’s next infant, the findings support the paternal effort hypothesis, in which males associate more with mothers in order to protect their offspring, rather than curry favor with the female. The research contributes to the broader anthropological question of why human fathers invest so much in offspring.

The authors of the paper, “Chimpanzee Fathers Bias Their Behavior Toward Their Offspring,” conducted their research based on long-term data from Gombe Stream National Park in Tanzania where long-term data collection is supported by the Jane Goodall Institute. Using more than 25 years of behavioral data digitized at the University of Minnesota, Duke University, the Lincoln Park Zoo, Franklin & Marshall College and The George Washington University, the researchers examined patterns based on 17 father chimpanzees and 49 mother-infant pairs to see if the males could recognize their offspring and if the male’s behavior was different around them. The researchers found the males associated with mothers of their offspring early in infancy and interacted with their infants more than expected.

“As anthropologists, we want to understand what patterns could have existed early in human evolution that help explain how human behavior evolved,” said Carson Murray, assistant professor of anthropology at the George Washington University and lead author of the paper. “This research suggests that males may sometimes prioritize relationships with their offspring rather than with potential mates. For a species without pair-bonds where it was assumed fathers didn’t know which infants were their own, this is an important finding.”

The significance of the finding lies in the evidence that chimpanzees, one of human’s closest living relatives, not only have paternal recognition but also invested in offspring rather than only focusing on future mating effort. The researchers found the males would spend time grooming and caring for their offspring.

“Our findings are not only further evidence that chimpanzee fathers recognize their offspring in a promiscuous species, but also that fathers behave differently around their offspring,” said Margaret Stanton, postdoctoral scientist at GW’s Center for the Advanced Study of Human Paleobiology and co-author of the paper.

The scientists stress that while the study is an important piece of research, it does not answer the overall question of how human paternal behavior evolved and is instead one piece of the anthropological puzzle.