Scientists name the commonest tropical tree species for the first time

Peer-Reviewed Publication

UNIVERSITY COLLEGE LONDON

 

A major international collaboration of 356 scientists led by UCL researchers has found almost identical patterns of tree diversity across the world’s tropical forests.

The study of over one million trees across 1,568 locations, published in Nature, found that just 2.2% of tree species make up 50% of the total number of trees in tropical forests across Africa, the Amazon, and Southeast Asia. Each continent consists of the same proportion of a few common species and many rare species.

While tropical forests are famous for their diversity, this is the first time that scientists have studied the commonest trees in the world’s tropical forests.

The scientists estimate that just 1,053 species account for half of the planet’s 800 billion tropical forest trees. The other half are comprised of 46,000 tree species. The number of rare species is extreme, with the rarest 39,500 species accounting for just 10% of trees.

Lead author Dr Declan Cooper (UCL Geography and UCL Centre for Biodiversity and Environment Research) said: “Our findings have profound implications for understanding tropical forests. If we focus on understanding the commonest tree species, we can probably predict how the whole forest will respond to today’s rapid environmental changes. This is especially important because tropical forests contain a tremendous amount of stored carbon, and are a globally important carbon sink.”

He continued: “Identifying the prevalence of the most common species gives scientists a new way of looking at tropical forests. Tracking these common species may provide a new way to characterise these forests and in the future possibly gauge a forest’s health more easily.”  

The researchers found strikingly similar patterns in the proportion of tree species that are common, at close to 2.2%, despite the tropical forests of the Amazon, Africa and Southeast Asia each having a unique history and differing contemporary environments.

The Amazon consists of a large region of connected forest, while Southeast Asia is a region of mostly disconnected islands. People only arrived in the Amazon around 20,000 years ago, but people have been living in African and Southeast Asian forests for more than twice that length of time. In terms of the contemporary environment, African forests experience a drier and cooler climate than the other two tropical forest regions. 

Given these striking differences, the near-identical patterns of tree diversity suggests that a fundamental mechanism may govern the assembly of tree communities across all the world’s tropical forests. The researchers are not yet able to say what that mechanism might be and it will focus future work on identifying it.

The estimates of common species derive from statistical analyses, which does not provide the names of the common trees. To overcome this, the scientists used a technique known as resampling to estimate which are the most likely names of the common species. Their list of 1,119 tree species names, the first list of common species of the world’s tropical forests, will allow researchers to focus their efforts on understanding the ecology of these species, which in turn can give scientists a short-cut to understand the whole forest.

See table below for a list of the most common tropical tree species.

 

Senior author, Professor Simon Lewis (UCL Geography and University of Leeds) said: “We wanted to look at tropical forests in a new way. Focusing on a few hundred common tree species on each continent, rather than the many thousands of species that we know almost nothing about, can open new ways to understand these precious forests. This focus on the commonest species should not take away from the importance of rare species. Rare species need special attention to protect them, but quick and important gains in knowledge will come from a scientific focus on the commonest tree species.”

The researchers assembled forest inventory data from intact tropical forests that hadn’t been affected by logging or fire. In each of 1,568 locations, teams identified and recorded every tree with a trunk greater than 10 centimetres in diameter, in a patch of forest, usually one hectare, which is a square of forest measuring 100 metres on each side.

Professor Lewis has been collecting and collating this data for 20 years. The effort is a collaboration of the largest plot networks across the Amazon (Amazon Tree Diversity Network; RAINFOR), Africa (African Tropical Rainforest Observatory Network, AfriTRON; Central African Plot Network), and Southeast Asia (Slik Diversity Network; T-FORCES), brought together for the first time for the published analysis. 

This collaboration across hundreds of researchers, field assistants, and local communities resulted in a total of 1,003,805 trees sampled, which included 8,493 tree species, across 2,048 hectares, equivalent to almost eight square miles of forest. The teams inventoried 1,097 plots in the Amazon totalling 1,434 hectares, 368 plots in Africa totalling 450 hectares, and 103 plots in Southeast Asia totalling 164 hectares.

This research was supported by the Natural Environmental Research Council.

Most common tropical forest tree species:

Continent	Scientific name	Local Names
Africa	Gilbertiodendron dewevrei	Limbali, otabo, agbabu, ekpagoi-eze
Africa	Greenwayodendron suaveolens	Africa Teak, atorewa, ẹ́wáé, nchua, eleku, agudugbu
Africa	Anonidium mannii	Junglesop, imido, asumpa, ọ̀ghẹ́dẹ́gbó
Africa	Petersianthus macrocarpus	Stinkwood tree; soap tree abalé, tun-tue, pèh, ésiv, kpa
Africa	Santiria trimera	adjouaba à racines aériennes, damzin, an-thanjka, kafe, poh, gólógóló.
Africa	Strombosia pustulata	itako, afina, poé, mba esogo
Africa	Tabernaemontana crassa	Adam's-apple flower, k-poŋgbo, opuko, patié patié, pete-pete
Africa	Staudtia kamerunensis	Niové, ichala, ọbara-okisi, íyìp ókōyò
Africa	Strombosiopsis tetrandra	Bwika, Mbazoo
Africa	Dichostemma glaucescens	Mangamba, Mongamba
Amazonia	Oenocarpus bacaba	Bacaba, Turu Palm
Amazonia	Eschweilera coriacea	matamatá
Amazonia	Iriartea deltoidea	bombona
Amazonia	Pentaclethra macroloba	pracaxi
Amazonia	Euterpe oleracea	açaí palm
Amazonia	Astrocaryum murumuru	murumuru
Amazonia	Geissospermum sericeum	quina-quina branca, pao pereira
Amazonia	Eperua falcata	bootlace tree, bi udu, wapa
Amazonia	Euterpe precatoria	mountain cabbage; açai, açaizeiro, açaí-do-amazonas, palmiche, wassaï, huasaí, manaca
Amazonia	Rinorea racemosa	branquinha
Southeast Asia	Shorea multiflora	yellow meranti
Southeast Asia	Tristaniopsis merguensis	Hill Tristania
Southeast Asia	Cotylelobium melanoxylon	Resak hitam; Khiam khaao; Resak tempurong; Giam tembaga
Southeast Asia	Dehaasia caesia	Magasil, Medang
Southeast Asia	Streblus ilicifolius	Jungle Holly, Merlimau
Southeast Asia	Shorea xanthophylla	seraya kuning barun
Southeast Asia	Shorea parvifolia	light red meranti, white lauan
Southeast Asia	Elateriospermum tapos	Perah, Buah Perah, Pogoh Nut, Tapos
Southeast Asia	Ixonanthes reticulata	Pagar Anak, Ten Men Tree, Inggir Burong, Nyiran Burong
Southeast Asia	Gluta oba	Rengas

 

Notes to Editors

For more information or to speak to the researchers involved, please contact Michael Lucibella, UCL Media Relations. T: +44 (0)75 3941 0389, E: m.lucibella@ucl.ac.uk

Declan Cooper, Simon Lewis, et. al, ‘Consistent patterns of common species across tropical tree communities’ will be published in Nature on Wednesday 10 January 2024, 16:00 UK time, 11:00 US Eastern Time, and is under a strict embargo until this time.

The DOI for this paper will be 10.1038/s41586-023-06820-z

Upon publication, the paper will be available at: https://www.nature.com/articles/s41586-023-06820-z

Additional material

• Declan Cooper’s academic profile
• Professor Simon Lewis’ academic profile
• UCL Geography
• UCL Faculty of Social & Historical Sciences

About UCL – London’s Global University

UCL is a diverse global community of world-class academics, students, industry links, external partners, and alumni. Our powerful collective of individuals and institutions work together to explore new possibilities.

Since 1826, we have championed independent thought by attracting and nurturing the world's best minds. Our community of more than 50,000 students from 150 countries and over 16,000 staff pursues academic excellence, breaks boundaries and makes a positive impact on real world problems.

The Times and Sunday Times University of the Year 2024, we are consistently ranked among the top 10 universities in the world and are one of only a handful of institutions rated as having the strongest academic reputation and the broadest research impact.

We have a progressive and integrated approach to our teaching and research – championing innovation, creativity and cross-disciplinary working. We teach our students how to think, not what to think, and see them as partners, collaborators and contributors.  

For almost 200 years, we are proud to have opened higher education to students from a wide range of backgrounds and to change the way we create and share knowledge.

We were the first in England to welcome women to university education and that courageous attitude and disruptive spirit is still alive today. We are UCL.

www.ucl.ac.uk | Follow @uclnews on Twitter | Read news at www.ucl.ac.uk/news/ | Listen to UCL podcasts on SoundCloud | View images on Flickr | Find out what’s on at UCL Minds

---

JOURNAL

Nature

DOI

10.1038/s41586-023-06820-z 

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Consistent patterns of common species across tropical tree communities

ARTICLE PUBLICATION DATE

10-Jan-2024

 

Ancient DNA reveals reason for high multiple sclerosis and Alzheimer’s rates in Europe

Peer-Reviewed Publication

UNIVERSITY OF CAMBRIDGE

 

IMAGE: 

THE NEW STUDY HAS FOUND THE GENES THAT SIGNIFICANTLY INCREASE A PERSON’S RISK OF DEVELOPING MULTIPLE SCLEROSIS (MS) WERE INTRODUCED INTO NORTH-WESTERN EUROPE AROUND 5,000 YEARS AGO BY SHEEP AND CATTLE HERDERS MIGRATING FROM THE EAST.

view more 

CREDIT: SAYOSTUDIO

Researchers have created the world’s largest ancient human gene bank by analysing the bones and teeth of almost 5,000 humans who lived across western Europe and Asia up to 34,000 years ago.

By sequencing ancient human DNA and comparing it to modern-day samples, the international team of experts mapped the historical spread of genes – and diseases – over time as populations migrated.

The ‘astounding’ results have been revealed in four trailblazing research papers published today (10 January 2024) in the same issue of Nature and provide new biological understanding of debilitating disorders.

The extraordinary study involved a large international team led by Professor Eske Willerslev at the Universities of Cambridge and Copenhagen, Professor Thomas Werge at the University of Copenhagen, and Professor Rasmus Nielsen at University of California, Berkeley and involved contributions from 175 researchers from around the globe.

The scientists found:

• The startling origins of neurodegenerative diseases including multiple sclerosis
• Why northern Europeans today are taller than people from southern Europe
• How major migration around 5,000 years ago introduced risk genes into the population in north-western Europe – leaving a legacy of higher rates of MS today
• Carrying the MS gene was an advantage at the time as it protected ancient farmers from catching infectious diseases from their sheep and cattle
• Genes known to increase the risk of diseases such as Alzheimer’s and type 2 diabetes were traced back to hunter gatherers
• Future analysis is hoped to reveal more about the genetic markers of autism, ADHD, schizophrenia, bipolar disorder, and depression

Northern Europe has the highest prevalence of multiple sclerosis in the world. A new study has found the genes that significantly increase a person’s risk of developing multiple sclerosis (MS) were introduced into north-western Europe around 5,000 years ago by sheep and cattle herders migrating from the east.

By analysing the DNA of ancient human bones and teeth, found at documented locations across Eurasia, researchers traced the geographical spread of MS from its origins on the Pontic Steppe (a region spanning parts of what are now Ukraine, South-West Russia and the West Kazakhstan Region).

They found that the genetic variants associated with a risk of developing MS ‘travelled’ with the Yamnaya people - livestock herders who migrated over the Pontic Steppe into North-Western Europe.

These genetic variants provided a survival advantage to the Yamnaya people, most likely by protecting them from catching infections from their sheep and cattle. But they also increased the risk of developing MS.

“It must have been a distinct advantage for the Yamnaya people to carry the MS risk genes, even after arriving in Europe, despite the fact that these genes undeniably increased their risk of developing MS,” said Professor Eske Willerslev, jointly at the Universities of Cambridge and Copenhagen and a Fellow of St John’s College, an expert in analysis of ancient DNA and Director of the project.

He added: “These results change our view of the causes of multiple sclerosis and have implications for the way it is treated.”

The age of specimens ranges from the Mesolithic and Neolithic through the Bronze Age, Iron Age and Viking period into the Middle Ages. The oldest genome in the data set is from an individual who lived approximately 34,000 years ago.

The findings provide an explanation for the ‘North-South Gradient’, in which there are around twice as many modern-day cases of MS in northern Europe than southern Europe, which has long been a mystery to researchers.

From a genetic perspective, the Yamnaya people are thought to be the ancestors of the present-day inhabitants of much of North-Western Europe. Their genetic influence on today’s population of southern Europe is much weaker.

Previous studies have identified 233 genetic variants that increase the risk of developing MS. These variants, also affected by environmental and lifestyle factors, increase disease risk by around 30 percent. The new research found that this modern-day genetic risk profile for MS is also present in bones and teeth that are thousands of years old.

“These results astounded us all. They provide a huge leap forward in our understanding of the evolution of MS and other autoimmune diseases. Showing how the lifestyles of our ancestors impacted modern disease risk just highlights how much we are the recipients of ancient immune systems in a modern world,” said Dr William Barrie, a postdoc in the University of Cambridge’s Department of Zoology and co-author of the paper.

Multiple sclerosis is a neurodegenerative disease in which the body’s immune system mistakenly attacks the ‘insulation’ surrounding the nerve fibres of the brain and spinal cord. This causes symptom flares known as relapses as well as longer-term degeneration, known as progression.

Professor Lars Fugger, a co-author of the MS study professor and consultant physician at John Radcliffe Hospital, University of Oxford, said: “This means we can now understand and seek to treat MS for what it actually is: the result of a genetic adaptation to certain environmental conditions that occurred back in our prehistory.”

Professor Astrid Iversen, another co-author based at the University of Oxford, said: “We now lead very different lives to those of our ancestors in terms of hygiene, diet, and medical treatment options and this combined with our evolutionary history means we may be more susceptible to certain diseases than our ancestors were, including autoimmune diseases such as MS.”

The Lundbeck Foundation GeoGenetics Centre – the resource underpinning the discoveries

The new findings were made possible by the analysis of data held in a unique gene bank of ancient DNA, created by the researchers over the past five years with funding from the Lundbeck Foundation.

This is the first gene bank of its kind in the world and already it has enabled fascinating new insights in areas from ancient human migrations, to genetically-determined risk profiles for the development of brain disorders.

By analysing the bones and teeth of almost 5,000 ancient humans, held in museum collections across Europe and Western Asia, the researchers generated DNA profiles ranging across the Mesolithic and Neolithic through the Bronze Age, Iron Age and Viking period into the Middle Ages. They compared the ancient DNA data to modern DNA from 400,000 people living in Britain, held in the UK Biobank.

“Creating a gene bank of ancient DNA from Eurasia’s past human inhabitants was a colossal project, involving collaboration with museums across the region,” said Willerslev.

He added: “We’ve demonstrated that our gene bank works as a precision tool that can give us new insights into human diseases, when combined with analyses of present-day human DNA data and inputs from several other research fields. That in itself is amazing, and there’s no doubt it has many applications beyond MS research.”

The team now plans to investigate other neurological conditions including Parkinson’s and Alzheimer’s diseases, and psychiatric disorders including ADHD and schizophrenia.

They have received requests from disease researchers across the world for access to the ancient DNA profiles, and eventually aim to make the gene bank open access.

The research was funded by a €8M grant from the Lundbeck Foundation, and conducted at the Lundbeck Foundation Geogenetics Centre at the University of Copenhagen.

Jan Egebjerg, Director of Research at the Lundbeck Foundation, said: "The rationale for awarding such a large research grant to this project, as the Lundbeck Foundation did back in 2018, was that if it all worked out, it would represent a trail-blazing means of gaining a deeper understanding of how the genetic architecture underlying brain disorders evolved over time. And brain disorders are our specific focus area." 

---

JOURNAL

Nature

DOI

10.1038/s41586-023-06618-z 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Elevated Genetic Risk for Multiple Sclerosis Originated in Steppe Pastoralist Populations

ARTICLE PUBLICATION DATE

10-Jan-2024

 

The extinction of the giant ape: a long-standing mystery solved

Peer-Reviewed Publication

MACQUARIE UNIVERSITY

 

IMAGE: 

AN ARTIST IMPRESSION OF A GROUP OF G. BLACKI WITHIN A FOREST IN SOUTHERN CHINA

view more 

CREDIT: GARCIA/JOANNES-BOYAU (SOUTHERN CROSS UNIVERSITY)

Giants once roamed the karst plains of southern China, three-metre tall apes weighing in at 250 kilograms. These very distant human ancestors – Gigantopithcus blacki – went extinct before humans arrived in the region, with few clues to why, and so far leaving around 2000 fossilised teeth and four jawbones as the only signs of their existence.

New evidence from this region published in Nature, uncovered by a team of Chinese, Australian and US researchers, demonstrates beyond doubt that the largest primate to walk the earth went extinct between 295,000 and 215,000 years ago, unable to adapt its food preferences and behaviours, and vulnerable to the changing climates which sealed its fate.

“The story of G. blacki is an enigma in palaeontology – how could such a mighty creature go extinct at a time when other primates were adapting and surviving? The unresolved cause of its disappearance has become the Holy Grail in this discipline,” says palaeontologist and co-lead author Professor Yingqi Zhang, from the Institute of Vertebrate Palaeontology and Palaeoanthropology at the Chinese Academy of Sciences (IVPP).

“The IVPP has been excavating for G. blacki evidence in this region for over 10 years but without solid dating and a consistent environmental analysis, the cause of its extinction had eluded us.”

Definitive evidence revealing the story of the giant ape’s extinction has come from a large-scale project collecting evidence from 22 cave sites spread across a wide region of Guangxi Province in southern China. The foundation of this study was the dating.

“It’s a major feat to present a defined cause for the extinction of a species, but establishing the exact time when a species disappears from the fossil record gives us a target timeframe for an environmental reconstruction and behaviour assessment,” says co-lead author, Macquarie University geochronologist Associate Professor Kira Westaway.

“Without robust dating, you are simply looking for clues in the wrong places.”

Six Australian universities contributed to the project. Macquarie University, Southern Cross University, Wollongong University and the University of Queensland used multiple techniques to date samples. Southern Cross also mapped G. blacki teeth to extract information on the apes’ behaviours. ANU and Flinders University studied the pollen and fossil bearing sediments in the cave respectively, to reconstruct the environments in which G. blacki thrived and then disappeared.

Six different dating techniques were applied to the cave sediments and fossils, producing 157 radiometric ages. These were combined with eight sources of environmental and behavioural evidence, and applied to 11 caves containing evidence of G blacki, and also to 11 caves of a similar age range where no G. blacki evidence was found.

Luminescence dating, which measures a light-sensitive signal found in the burial sediments that encased the G. blacki fossils, was the primary technique, supported by uranium series (US) and electron-spin resonance (US-ESR) dating of the G. blacki teeth themselves.

“By direct-dating the fossil remains, we confirmed their age aligns with the luminescence sequence in the sediments where they were found, giving us a comprehensive and reliable chronology for the extinction of G. blacki,” says Southern Cross University geochronologist Associate Professor Renaud Joannes-Boyau.

 

Using detailed pollen analysis, fauna reconstructions, stable isotope analysis of the teeth and a detailed analysis of the cave sediments at a micro level, the team established the environmental conditions leading up to when G blacki went extinct. Then, using trace element and dental microwear textural analysis (DMTA) of the apes’ teeth, the team modelled G. blacki’s behaviour while it was flourishing, compared to during the species’ demise.

 

“Teeth provide a staggering insight into the behaviour of the species indicating stress, diversity of food sources, and repeated behaviours,” says Associate Professor Joannes-Boyau

 

The findings show G.blacki went extinct between 295,000 and 215,000 years ago, much earlier than previously assumed. Before this time, G. blacki flourished in a rich and diverse forest.

 

By 700,000 to 600,000 years ago, the environment became more variable due to the increase in the strength of the seasons, causing a change in the structure of the forest communities.

 

Orangutans (genus Pongo) – a close relative of G. blacki – adapted their size, behaviour and habitat preferences as conditions changed. In comparison, G. blacki relied on a less nutritious back up food source when its preferences were unavailable, decreasing the diversity of its food. The ape became less mobile, had a reduced geographic range for foraging, and faced chronic stress and dwindling numbers.

 

“G. blacki was the ultimate specialist, compared to the more agile adapters like orangutans,  and this ultimately led to its demise,” says Professor Zhang.

 

Associate Professor Westaway says: “With the threat of a sixth mass extinction event looming over us, there is an urgent need to understand why species go extinct.

“Exploring the reasons for past unresolved extinctions gives us a good starting point to understand primate resilience and the fate of other large animals, in the past and future.”

 

  

Digging into the hard cemented cave sediments containing a wealth of fossils and evidence of G. blacki

Facing out of Zhang Wang Cave across the alluvial plain

The G. blacki bearing cave of Zhang Wang lies 150 m above the valley floor making for a tough climb every day to conduct excavations

CREDIT

Kira Westaway (Macquarie University)

Karst landscape panorama in southern China

 

Cone and towering karst forms a dense network of mountains riddled with caves containing G. blacki evidence

CREDIT

Joannes-Boyau (Southern Cross University)

A drones-eye view of Mulan Mountain 

The location of many caves including two G. blacki bearing caves

CREDIT

Yingqi Zhang (IVPP- CAS)

JOURNAL

Nature

DOI

10.1038/s41586-023-06900-0 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

The demise of the giant ape Gigantopithecus blacki

ARTICLE PUBLICATION DATE

10-Jan-2024

COI STATEMENT

The authors declare no conflicts. This research was funded by the Australian Research Council with a Discovery grant to KEW, YZ, SH, RC (DP170101597), Future Fellowship (FT180100309) to MWM, LIEF (LE130100115) to GG and GP, and by the Chinese Academy of Sciences Strategic Priority Research grant to YZ, KEW and RJB (XDB26030303). Aspects of the ESR dating study on quartz have been covered by the Ramón y Cajal Fellowship RYC2018-025221-I granted to MD and funded by MCIN/AEI/ 10.13039/501100011033 and “ESF Investing in your future”. PR would like to thank the Max Planck Society for funding and support. The DMTA and microstratigraphical analyses was supported by W. V. Scott Estate Charitable Trust Fund (123402902) and a Ruggles-Gates Scholarship (125201851) by the Royal Anthropological Institute (UK) grants to JKL. The research in the BB Basin was funded by the National Social Science Foundation of China (20&ZD246) and the BaGui Scholars Project of the Guangxi.

 

A beating biorobotic heart aims to better simulate valves

Peer-Reviewed Publication

CELL PRESS

 

IMAGE: 

SCIENTISTS CRAFTED A BIOROBOTIC HEART SIMULATOR BY REPLACING THE HEART MUSCLE OF A BIOLOGICAL HEART’S LEFT CHAMBER WITH A SOFT ROBOTIC PUMP

view more 

CREDIT: MANISHA SINGH

Combining a biological heart and a silicone robotic pump, researchers created a biorobotic heart that beats like a real one, with a focus on a valve on the left side of the heart. The heart valve simulator, presented on January 10 in the journal Device, can mimic the structure, function, and motion of a healthy or diseased heart, allowing surgeons and researchers to demonstrate various interventions while collecting real-time data.

“The simulator has a huge benefit as a research tool for those who study different heart valve conditions and interventions,” says senior author and biomedical engineer Ellen Roche of the Massachusetts Institute of Technology. “It can serve as a surgical training platform for clinicians, medical students, and trainees, allow device engineers to study their new designs, and even help patients better understand their own disease and potential treatments.”

Before new interventions reach humans, they undergo rigorous testing in heart simulators and animal subjects. However, current heart simulators don’t completely capture the complexity of a heart and have a short shelf-life of two to four hours. Animal studies are expensive and time consuming, and the findings may not always translate to humans. The biorobotic heart can bridge these gaps as a less expensive method with a shelf life of months.

The researchers focused on mitral regurgitation, a disorder in which the valve between the left heart chambers doesn’t close properly—resulting in a leaky heart valve where blood can flow backwards. This condition, affecting about 24.2 million people worldwide, can cause shortness of breath, swelling in the limbs, and heart failure. Given the intricacy of the valve’s structure, surgeries to correct the disorder are highly complex, highlighting a need for effective technology and precise surgical techniques.

To better understand the mitral valve in healthy and diseased states, the team built a biorobotic heart based on a pig heart. The researchers replaced the heart muscle in the left chamber with a silicone-made soft robotic pump system actuated by air. When inflated, the system twists and squeezes the heart like real heart muscle, pumping artificial blood through a mock circulation system and simulating the beat of a biological heart.

When the team damaged the mitral valve in the biorobotic heart, it showed characteristics of a leaky heart valve. The team then had cardiac surgeons correct the damage with three different techniques: anchoring the flailing valve leaflet tissue with artificial chords, replacing the valve with a prosthetic valve, and implanting a device to help valve leaflet closing.

All three procedures were successful, bringing the pressure, flow, and heart function to normal. The system also enabled the research team to collect real-time data during surgery and is compatible with current imaging technologies used in the clinics. Because the artificial blood used in the system is clear, it also allows direct visualization of the procedure. The findings demonstrated the device as a new heart model.

“It was really interesting for the surgeons to see every step,” says Roche. “When you’re working with patients, you can’t visualize the process because there’s blood in the heart.” She foresees their heart model as a realistic environment for cardiac surgery training and practice.

Next, the team aims to optimize the current biorobotic heart system by shortening the production time and lengthening the shelf life even more. Instead of using a pig heart, they’re also exploring 3D printing technology to recreate a synthetic human heart for the system.

“Our biorobotic heart may help improve the device design cycle, allow rapid iterations, get things approved by regulatory bodies, and launch them into the market quickly,” says Roche. “Expediting and improving these processes will ultimately benefit patients.”

###

This work was supported by the National Science Foundation, the Philips/MIT award, and the MathWorks Fellowship. Please see the text for conflict-of-interest information.

Device, Park et al. “Biorobotic hybrid heart as a benchtop cardiac mitral valve simulator” https://www.cell.com/device/fulltext/S2666-9986(23)00357-5

Device (@Device_CP), is a physical science journal from Cell Press along with Chem, Joule, and Matter. Device aims to be the breakthrough journal to support device- and application-oriented research from all disciplines, including applied physics, applied materials, nanotechnology, robotics, energy research, chemistry, and biotechnology, under a single title that focuses on the integration of these diverse disciplines in the creation of the cutting-edge technology of tomorrow. Visit http://www.cell.com/device/home. To receive Cell Press media alerts, contact press@cell.com.

---

JOURNAL

Device

DOI

10.1016/j.device.2023.100217 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Human tissue samples

ARTICLE TITLE

Biorobotic hybrid heart as a benchtop cardiac mitral valve simulator

ARTICLE PUBLICATION DATE

10-Jan-2024

Joking apart: What men and women find funny

Humor preferences may reflect how social worlds of the sexes are organized, study finds

Peer-Reviewed Publication

DE GRUYTER

Men rate visual jokes more highly than women do, whereas women prefer jokes that involve political commentary or the dynamics of close relationships, a new study of print cartoons dating from 1930-2010 finds.

The research, led by Professor Robin Dunbar of the University of Oxford and published in the De Gruyter journal Humor, also found some similarities, with both sexes enjoying cartoons that delve into the complexities of romance. 

Study data was collected from 3,380 people attending an exhibit of print cartoons by well-known artists at The Cartoon Museum, London. The humor of such cartoons is strongly visual and often uses a verbal caption to add context and, in many instances, the punchline.

The researchers arranged cartoons of varying complexity in 18 pairs and asked study participants to rate which joke was funnier. The responses were then analyzed according to the ‘mentalizing’ content of the cartoons, participants' age and sex, and when the cartoon was first published.  

More complex jokes with more ‘mindstates’ (“I know what she’s thinking about what he’s saying”) were considered funnier than those that relied on simpler, more slapstick humor. However, such jokes only worked up to a limit of three levels with additional mindstates falling flat: the 2D medium cannot ably handle more detailed reveals like moving 3D images with an additional time perspective.

“Like verbal jokes, cartoons are funnier the more mindstates, essentially characters, they involve,” says Professor Dunbar. "But there is a limit after which they become incomprehensible.”

Participant age didn’t significantly affect the humor rating given to a cartoon, and nor did the time since its publication.

Both sexes clearly considered visual jokes using puns or wordplay and social commentary jokes about domestic marital relationships funnier than any other topic. Men and women were least enthusiastic about political jokes.

However, some modest differences were found between the sexes with women indicating a greater preference for jokes about domestic situations and political commentary while men preferred situational (slapstick) and visual jokes.

This finding may reflect how men and women manage their relationships, the authors surmise. “We argue that these differences in humor preference arise from the remarkable differences in social style of the two sexes,” Professor Dunbar says. “This explanation has previously been overlooked because psychologists and others have concentrated on IQ-type differences, which are minimal.”

---

JOURNAL

Humor - International Journal of Humor Research

DOI

10.1515/humor-2023-0111 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Why cartoons make (some of) us smile

ARTICLE PUBLICATION DATE

5-Jan-2024