Orangutans nap to make up for lost sleep

New study reveals that wild orangutans recover from sleep loss with daytime naps, much like humans do

Max Planck Institute of Animal Behavior

Facebook

XLinkedInWeChatBlueskyMessageWhatsAppEmail

 

image: 

Cissy, a Sumatran orangutan mother is taking a nap in her day nest.

view more 

Credit: Natasha Bartalotta / Suaq

Anybody who has ever struggled to get enough sleep knows just how much in life can interfere with our rest, and just how detrimental this can be to our health and happiness. Researchers from the Max Planck Institute of Animal Behavior (MPI-AB) and the University of Konstanz in Germany, in collaboration with scientists at the Universitas Nasional in Indonesia, have found that some of our closest living relatives, orangutans, face similar issues, and have a very familiar coping strategy: napping.

“Moving through the canopy, finding food, solving problems, navigating social relationships; these are all tiring and cognitively demanding tasks,” says Alison Ashbury, the study’s first author. “When an orangutan doesn’t get enough sleep, it does what any sleep-deprived human might do: it climbs into bed, lies down, and takes a nap.”

Tracking sleep in the treetops

The research team worked in the Indonesian rainforest to examine the sleep patterns of wild adult orangutans, which have never been studied specifically for how they solve challenges of sleep. Doing so opened a window into understanding how sleep evolved in great apes and our own human ancestors. The scientists collected data from 53 adult orangutans over 14 years at the Suaq Balimbing Monitoring Station in Sumatra, recording in total 455 days and nights of orangutan behavior.

But tracking sleep in the wild provided logistical challenges for human observers. Much like us, wild orangutans sleep in beds, known as “nests”, which provide a safe place for resting. Every night, an adult orangutan will settle in a spot high up in the rainforest canopy. There, it will spend about ten minutes building a nest: bending, breaking, and weaving together tree branches to create a solid platform, complete with a leafy mattress and pillow for comfort. Mothers share nests with their nursing young, but otherwise, with very few exceptions, adult orangutans sleep alone. At dawn, they leave their nests to start the day.

 “From our point of view on the ground, we usually can’t see orangutans at all in their night nests, but we can hear them rustling around, getting comfortable,” says Caroline Schuppli, the study’s senior author and a group leader at MPI-AB. “Eventually, everything goes quiet and still. And the reverse happens in the morning.”

It was that silent stretch in the middle that researchers called the “sleep period” and that they used as an indicator of sleep. They found that orangutans’ sleep periods were, on average, nearly 13 hours long. In the paper, the team cited past work in both captive orangutans and wild baboons that showed strong correlations between sleep period and actual time spent sleeping. This suggests that, although the team couldn’t directly measure sleep itself among these wild orangutans, the sleep period that they could measure is a robust indicator of actual sleep.

The researchers also found that several factors were associated with shorter overnight sleep periods: going to sleep near other orangutans, colder nighttime temperatures, and further daily travel.

“We thought it was really interesting that just being near other orangutans when building a night nest was linked to shorter sleep periods,” says Ashbury, a scientist at MPI-AB and the University of Konstanz. “Imagine you stay up late hanging out with your friends, or your roommate is snoring so loudly in the morning that you get up early. I think it’s a bit like that. They’re prioritizing being social over sleeping, or their sleep is being disrupted by others nearby, or even both.”

The power of the power nap

To understand how orangutans recover from lost sleep, the team analyzed how the duration of nap periods changed in relation to the previous night’s rest. They found a clear compensatory effect: orangutans’ nap periods were longer on days after they had shorter night time sleep periods, and when they did nap, they napped 5 to 10 minutes longer for every hour less sleep the night before. 

“For people, even a short nap can have significant restorative effects,” says co-author Meg Crofoot, director at MPI-AB and a professor at the University of Konstanz. “It’s possible that these naps are helping orangutans reset physiologically and cognitively after a poor night’s sleep, just like they do in humans.”

Day nests are central to this strategy. Compared to orangutans in many other populations, the Suaq orangutans more frequently build nests during the day. These nests are simpler and faster to build than night nests, typically taking under two minutes, but still offer a stable and secure place to nap.

“Day nests are less sophisticated, have fewer comfort elements, and are made quicker than night nests,” says Schuppli. “But even so, when we’re able to see an orangutan resting in a day nest, we see that their bodies are relaxed and their eyes are closed. They really do appear to be sleeping.”

The researchers believe these findings may also relate to orangutan cognition. The Suaq population is known for its tool use and cultural complexity—traits that may require robust mechanisms to buffer against sleep deprivation.

“Among all studied orangutan populations, the Suaq orangutans arguably exhibit the widest range of cognitively demanding behaviors,” says Schuppli who is the research director at the Suaq research site. “This may be linked to their relatively high propensity for daytime nest use. Either they need these high-quality naps to meet their cognitive demands, or their cognitive abilities can come about because they take high-quality naps in day nests so often.”

This napping strategy may also be made possible by their semi-solitary lifestyle. While primates in cohesive groups must constantly coordinate with others, orangutans are free to nap when and where they choose. On 41% of observed days, orangutans took at least one nap, and they averaged a total nap period of 76 minutes.

Studying sleep in the wild

This study contributes to a growing body of evidence that wild animals must trade-off between their need for sleep and their need to fulfil other social and ecological demands. While the neural and physiological processes and the benefits of sleep are well-studied in laboratory settings, Crofoot, who is leading an ERC-funded project on sleep in the wild, points out: “Studying sleep in the wild, in the natural social and ecological conditions under which it evolved, is important to broadening our understanding of the evolutionary origins and the ultimate functions of sleep. Why did animals, from humans to primates to spiders to jellyfish, evolve to spend such large portions of their lives in this vulnerable unconscious state? If we’re going to answer this question, we need to bring sleep research out of the lab and into the field. Studies such as this one contribute to that effort.”

---

Journal

Current Biology

DOI

10.1016/j.cub.2025.05.053 

Method of Research

Observational study

Subject of Research

Animals

Article Title

Wild orangutans maintain sleep homeostasis through napping, counterbalancing socio-ecological factors that interfere with their sleep

Article Publication Date

25-Jun-2025

 

Pervasive surveillance of people is being used to access, monetize, coerce, and control

Trinity College Dublin

Facebook

XLinkedInWeChatBlueskyMessagWhatsAppEmail

]

New research has underlined the surprising extent to which pervasive surveillance of people and their habits is powered by computer vision research – and shone a spotlight on how vulnerable individuals and communities are at risk.

Analyses of over 40,000 documents, computer vision (CV) papers and downstream patents spanning four decades has shown a five-fold increase in the number of computer vision papers linked to downstream surveillance patents. The work also highlights the rise of obfuscating language that is used to normalise and even hide the existence of surveillance. 

The research, conducted by Dr Abeba Birhane and collaborators from Stanford University, Carnegie Mellon University, University of Washington and Allen Institute for Artificial Intelligence (AI2), has just been published in leading international journal Nature. Dr Birhane directs the AI Accountability Lab (AIAL) in the ADAPT Research Ireland Centre at the School of Computer Science and Statistics in Trinity College Dublin.

Dr Birhane said: “This work provides a detailed, systematic understanding of the field of computer vision research and presents a concrete empirical account that reveals the pathway from such research to surveillance and the extent of this surveillance.”

“While the general narrative is that only a small portion of Computer vision research is harmful, what we found instead is pervasive and normalised surveillance.”

Among the key findings were that: 

1. The field has evolved linguistically, with a trajectory away from generic papers in the 1990s towards a heightened focus on analysing semantic categories and humans and their behaviours in the 2010s 

2. Surveillance has been increasingly hidden by jargon and obfuscating language that distracts from people being at the heart of the surveillance 

3. Rights to privacy and certain freedoms are under threat

Additionally, the work indicated the top institutions producing the most surveillance are: 1. Microsoft; 2.Carnegie Mellon University; 3. MIT; 4. University of Illinois Urbana-Champaign; 5. Chinese University of Hong Kong, and the top nations are: 1. US; 2. China; 3. UK.

Dr Birhane added: “Linguistically the field has increasingly adapted to obfuscate the existence and extent of surveillance. One such example is how the word ‘object’ has been normalised as an umbrella term which is often synonymous with ‘people’.”

“The most troublesome implications of this are that it is harder and harder to opt out, disconnect, or to ‘just be’, and that tech and applications that come from this surveillance are often used to access, monetise, coerce, and control individuals and communities at the margins of society.”

“Due to pervasive and intensive data gathering and surveillance, our rights to privacy and related freedoms of movement, speech and expression are under significant threat.” 

However, the researchers stress that a major, more hopeful takeaway from the work is that nothing is written in stone, and that this large-scale, systematic study can aid regulators and policy makers in addressing some of the issues. 

Dr Birhane said: “We hope these findings will equip activists and grassroots communities with the empirical evidence they need to demand change, and to help transform systems and societies in a more rights-respecting direction.” 

“CV researchers could also adopt a more critical approach, exercise the right to conscientious objection, collectively protest and cancel surveillance projects, and change their focus to study ethical dimensions of the field, educate the public, or put forward informed advocacy.”

Dr Birhane has recently been awarded around €200,000 from the European Artificial Intelligence & Society Fund to support research at the AIAL.

---

Journal

Nature

DOI

10.1038/s41586-025-08972-6 

 

New Global Index Aims to Help People and Nature Thrive Together

Researchers at Oxford University join the United Nations Development Programme to propose an optimistic, practical approach to inspire stronger action on nature.

Oxford, 25 June 2025 — As the world faces an escalating planetary crisis, a new paper published today in Nature offers something we don’t often hear - hope. Rather than focussing on what we’re doing wrong, the paper proposes a bold new way forward; a global framework that measures how well people and nature are thriving together.

The paper, titled 'An Aspirational Approach to Planetary Futures', is the result of a groundbreaking international collaboration led by the United Nations Development Programme and researchers, including Oxford University’s Professor Yadvinder Malhi and Samira Barzin from the Leverhulme Centre for Nature Recovery, Peter Frankopan, Molly Grace, and Oxford Martin School Fellows Erle Ellis, Sandra Diaz, and Hannah Ritchie.

The team calls for the creation of a 'Nature Relationship Index' to sit alongside the Human Development Index (HDI). The aim is to track how countries are improving human relationships with the rest of life on Earth, including a thriving and accessible nature, using natural resources responsibly, and protecting ecosystems – turning these into measurable goals for progress.

Their message is simple yet radical: the way we talk about and measure progress must change, because current measures like GDP, and even the HDI, do not account for how we relate to the rest of life on Earth. Without raising the bar for progress to include all life on Earth, nature’s decline will continue, with consequences for all of us.

'For decades, the human development approach has inspired global progress by focusing on people’s abilities to lead the lives they value and have reason to value: living longer, healthier lives with access to knowledge, and enjoying a decent standard of living,' said Pedro Conceição, Director of the UNDP Human Development Report Office, and contributing author, 'However, in the face of today’s dangerous planetary change, we must raise our ambitions, and that means envisioning progress and development to include healthy and mutually beneficial relationships with the living world'.

At the core of this vision is a bold new idea: the Nature Relationship Index (NRI)—a global metric designed to complement the HDI, and capture the quality of a nation’s relationship with nature. It would assess how well countries are caring for ecosystems, ensuring equitable access to nature, and protecting it from harm. In other words: countries investing in shared spaces for nature and people, clean air and water, and restoring ecosystems could see its NRI rise, rewarding positive action rather than just recording decline.

The NRI is being developed with the aim of debuting in the 2026 Human Development Report, with the long-term goal of regular country-level updates, just like the HDI. The hope? To turn the tide—from reacting to ecological collapse, to actively building a future where both people and the planet can flourish.

'This isn’t the usual environmental messaging about limiting the damage or staving off disaster,' said Erle Ellis, lead author of the paper and professor at the University of Maryland Baltimore County and Oxford Martin School Fellow at the University of Oxford, 'What we’re proposing is a shift from narratives of environmental harm and failure to stories and evidence that our societies have the capabilities to produce better futures for all life on Earth – and that in many ways we already have. By expanding human development to include healthy relationships among people and the rest of life on Earth, we hope to motivate whole new levels of collaboration and innovation across the planet'.

Rather than leaning solely on fear-driven warnings of environmental doom, the paper urges a shift to storytelling and strategies grounded in human potential—our shared aspirations for clean air, thriving wildlife, green spaces for everyone, and connection. These, the authors argue, are powerful tools for unlocking global action.

Yadvinder Malhi, co-author and Director of the Leverhulme Centre for Nature Recovery at the University of Oxford, highlighted the urgency and opportunity behind the initiative: 'There is a need for clear-eyed but hopeful and actionable visions of the future. The planetary crisis is profound, but it’s also an invitation. An invitation to rethink our relationship with the Earth, not as relentless consumers of a commodified and exploited nature, but as integral participants in our mutual co-flourishing with the rest of the natural world.'

This new framework could mark a crucial turning point for global development. By embedding this aspirational vision into policies and everyday decisions, the authors call on all of us—governments, communities, and individuals—to take real, measurable steps towards making life on this planet better for all of us. Because the future we want depends on what we do today.

A future where people and nature thrive together is possible. The question now is: will we make it happen?

-End-

The Nature Relationship Index at a glance

• Expands the aspirational space of development to include thriving human-nature relationships.
• Provides a globally accepted, values-based metric to guide and celebrate progress toward more sustainable futures.
• Aims to shift focus from avoiding environmental harm to fostering aspirational, positive relationships with nature.
• Seeks to empower societies to pursue a future where people and nature thrive together.
• Inspired by the HDI, the NRI tracks open-ended progress.
• Measures how well societies balance human development with caring, sustainable interactions with nature.
• Three Core Dimensions of the NRI:
  • Nature is Thriving and Accessible: Measures extent and access to natural areas.
  • Nature is Used with Care: Evaluates the sustainability of resource use and impacts like emissions.
  • Nature is Safeguarded: Assesses legal and institutional commitments to protecting nature.

Notes for Editors

• Paper URL – www.nature.com/articles/s41586-025-09080-1
• DOI – 10.1038/s41586-025-09080-1
• For more information and interviews with the authors, please contact: 

E: Lizzie Dunthorne lizzie.dunthorne@admin.ox.ac.uk University of Oxford 

Video explainers

For use in the context of articles and content focused on the Nature Recovery Index only. Credit: @NatureRecovery

• Professor Yadvinder Malhi and the Nature Relationship Index - Here Yadvinder explains why he is excited about the NRI.
• Professor Erle Ellis and the Nature Relationship Index - Here Erle explains the goal of the NRI.

About the University of Oxford

Oxford University has been placed number 1 in the Times Higher Education World University Rankings for the ninth year running, and number 3 in the QS World Rankings 2024. At the heart of this success are the twin-pillars of our ground-breaking research and innovation and our distinctive educational offer.

Oxford is world-famous for research and teaching excellence and home to some of the most talented people from across the globe. Our work helps the lives of millions, solving real-world problems through a huge network of partnerships and collaborations. The breadth and interdisciplinary nature of our research alongside our personalised approach to teaching sparks imaginative and inventive insights and solutions.

Through its research commercialisation arm, Oxford University Innovation, Oxford is the highest university patent filer in the UK and is ranked first in the UK for university spinouts, having created more than 300 new companies since 1988. Over a third of these companies have been created in the past five years. The university is a catalyst for prosperity in Oxfordshire and the United Kingdom, contributing £15.7 billion to the UK economy in 2018/19, and supports more than 28,000 full time jobs.

About the United Nations Development Programme (UNDP)

UNDP is the leading United Nations organization fighting to end the injustice of poverty, inequality, and climate change. Working with our broad network of experts and partners in 170 countries, we help nations to build integrated, lasting solutions for people and planet. Learn more at undp.org/nature or follow @UNDP and @UNDP Nature.

---

Journal

Nature

DOI

10.1038/s41586-025-09080-1 

Article Title

An Aspirational Approach to Planetary Futures

 

New study shows how biomass changed over 500 million years

Stanford University

FacebookX

LinkedInWeChatBlueskyMessageWhatsAppEmail

In a first-of-its-kind study, Stanford researchers have measured how the abundance of ocean life has changed over the past half-billion years of Earth’s history. 

Overall, the total mass of marine organisms has generally increased over the past 500 million years, the study showed, albeit with setbacks after major extinction events. The findings align with evidence for a similar rise in marine biodiversity – the total variety of organisms – over the past half-eon from studies dating as far back as the 19th century, suggesting an evolutionary connection between biomass and biodiversity. The research appears in Current Biology June 25.

“Understanding the amount of biomass is important because it represents key traits about an ecosystem that are not captured by the number of species or even the number of niches that they fill,” said study lead author Pulkit Singh, a postdoctoral scholar in Earth and Planetary Sciences in the Stanford Doerr School of Sustainability. “But as we move into the past, our measurements of biomass are very limited, so that was the big gap in biological history we wanted to fill with our study.”

The results come from an in-depth compilation and review of data from thousands of rock samples containing skeletal remains, which in the oceanic environment primarily comprise shells of animals, certain kinds of algae, and single-celled organisms called protists. Fossils with skeletal remains recorded the amount of biomass – the material comprising and produced by living things – that was preserved across different geological intervals. Biomass reveals the productivity of an ecosystem, indicating the amount of energy (food) present and the quantity of organisms that a system can support. Productivity, in turn, speaks to ecosystem health, and in the broad aggregate, to planetary health. 

Researchers have long shied away from attempting to measure biomass, given the immense effort required to gather relevant data and the possibility that data wouldn’t be sufficient for revealing meaningful patterns. Singh undertook the challenge, devoting several years to compiling data published over decades, as well as adding new data from his own samples.

“The first quantitative effort to document and graph biodiversity across geological time was made in 1860, but until Pulkit’s paper, there’s never been a corresponding biomass-across-time paper,” said senior study author Jonathan Payne, the Dorrell William Kirby Professor of Earth and Planetary Sciences at Stanford. “I’m impressed by his intellectual courage to go and take a chance on a project like this.”

Picking through the past

For the study, Singh and colleagues considered more than 7,700 marine limestone samples from all over the world spanning the past 540 million years that have been documented across more than 100 scientific studies. The research team relied on data gathered via a standard method known as petrographic point-counting to assess the percentage of each sample that contained skeletal remains. The time-consuming technique involves cutting and polishing rocks very thinly so light can shine through them, then examining the thin sections of rock samples under a microscope to quantify their composition. 

During the Cambrian, the earliest period sampled that started about 540 million years ago, researchers found fewer than 10 percent of the rocks, on average, were composed of shell material. As the Cambrian gave way to the Ordovician Period about 485 million years ago, that percentage climbed, partly reflecting the “Cambrian Explosion,” when life on Earth dramatically expanded in diversity and complexity. Calcifying sponges were initially notable contributors to biomass but were later leapfrogged by newly evolved echinoderms – including ancestors of modern-day starfish – and marine arthropods, including extinct trilobites and ancestors of crabs. 

Throughout much of the next 230 million years, shell content soared well above 20 percent, with a significant decrease during one of the “Big Five” mass extinction events in the Late Devonian, about 375 to 360 million years ago. The biggest drop in living history then struck about 250 million years ago during the “Great Dying,” the Permian-Triassic extinction, when shell percentage plummeted to about 3 percent. 

Life recovered, and except for subsequent significant mass extinctions – the end-Triassic extinction about 200 million years ago and the Cretaceous-Paleogene about 66 million years ago, which infamously killed off the non-avian dinosaurs – biomass has boomed in our current geological era, the Cenozoic, with shells exceeding 40 percent of rock volume, thanks in part to substantial contributions from mollusks and corals. “The overall pattern that we were able to capture is that it’s a gradual increase,” Singh said. 

One of the biggest challenges in conducting the study involved telling whether the increasing shell content in rocks truly signaled a rise in bio-abundances over time or if other ecological factors, such as a decrease in shell-boring and -destroying predators, or methodological sample biases were behind the pattern.

To cross-check their results, the researchers performed a series of rigorous tests. They sorted samples by depositional environment of shallow or deep water, factoring in how shell remains accumulate more frequently in better-populated shallow waters. The researchers also sorted samples by different latitudes and locations and shapes of the predecessors of today’s continents. Through it all, the signal remained strongly consistent across water depths, latitudes, and geologic settings.

“The more tests we did and the more we divided our dataset, we realized that these big biological patterns we were seeing stayed over time,” Singh said. 

Life-altering events

As to why marine life has generally increased, evidence points to the parallel trends in greater diversity. With marine organisms becoming more specialized and more variable in their specializations, more energy can be extracted from available nutrients and food resources. This enhanced nutrient recycling starts with the autotrophs, such as phytoplankton, that photosynthetically “feed” on sunlight and ends with decomposers returning nutrients to the environment that autotrophs take up. 

“The overall idea is that there is more food available in ecosystems and because of that, the ecosystems can support more life, there’s more energy available, and that leads to greater abundance expressed in biomass,” Singh said. 

Whether or not the plenitude seen over the last hundreds of millions of years will persist could be in question, considering impacts from human activities. Although people have caused fertilizer runoff, overfishing, ocean acidification, and more during a mere blip in geological time, scientists have widely documented an ongoing, human-driven sixth mass extinction. Accumulating losses in biodiversity could potentially reduce biomass, and vice versa – a signal that perhaps could be captured in the fossil record currently being laid down. 

“From our study’s perspective, modern times are quite complicated given the extent of human activity that’s rapidly altering conditions planetwide, including in the oceans,” said Payne, who is also a senior fellow at the Stanford Woods Institute for the Environment. “But our findings show that overall biomass is linked to biodiversity and that losses in biodiversity may suppress productivity for geologically meaningful intervals, adding one more argument of why conserving biodiversity is essential for the health of humans and our planet.” 

Additional Stanford co-authors include Jordan Ferré, Bridget Thrasher, and Pedro Monarrez. Other study co-authors are from the Virginia Polytechnic Institute and State University, King Fahd University of Petroleum and Minerals, Cantrell GeoLogic LLC, Trinity University, and the University of Ferrara. The research was supported by a Frontier Research in Earth Sciences grant from the U.S. National Science Foundation. 

---

Journal

Current Biology

DOI

10.1016/j.cub.2025.06.006 

Article Title

Macroevolutionary coupling of marine biomass and biodiversity across the Phanerozoic

Article Publication Date

25-Jun-2025

 

Estimated 2023-2024 COVID-19 vaccine effectiveness in adults

JAMA Network Open

Facebook

XLinkedInWeChatBlueskyMessageWhatsAppEmail

About The Study:

 In this case-control study of vaccine effectiveness, 2023-2024 COVID-19 vaccines were estimated to provide additional effectiveness against medically attended COVID-19, with the highest and most sustained estimates against critical illness. These results highlight the importance of receiving recommended COVID-19 vaccination for adults 18 years or older. 

Corresponding Author: To contact the corresponding author, Ruth Link-Gelles, PhD, MPH, email hzt7@cdc.gov.

To access the embargoed study: Visit our For The Media website at this link https://media.jamanetwork.com/

(doi:10.1001/jamanetworkopen.2025.17402)

Editor’s Note: Please see the article for additional information, including other authors, author contributions and affiliations, conflict of interest and financial disclosures, and funding and support.

#  #  #

Embed this link to provide your readers free access to the full-text article 

 http://jamanetwork.com/journals/jamanetworkopen/fullarticle/10.1001/jamanetworkopen.2025.17402?utm_source=For_The_Media&utm_medium=referral&utm_campaign=ftm_links&utm_term=062525

About JAMA Network Open: JAMA Network Open is an online-only open access general medical journal from the JAMA Network. On weekdays, the journal publishes peer-reviewed clinical research and commentary in more than 40 medical and health subject areas. Every article is free online from the day of publication. 

 

---

Journal

JAMA Network Open