Selfies and other third-person photos help us capture the meaning of moments

Peer-Reviewed Publication

SOCIETY FOR PERSONALITY AND SOCIAL PSYCHOLOGY

Imagine you are eating your dream meal and want to commemorate the moment: Should you snap a picture of the food by itself or take a selfie with your partner while you eat? New research suggests that people use first-person photography, taking a photo of the scene from one’s own perspective, when they want to document a physical experience, but opt for third-person photos, depicting themselves in the scene (like selfies), to capture the deeper meaning of events.

Previous research has focused how the photo-taker wants to present themselves to others. The current research, published today in Social Psychological and Personality Science, also considers people who are taking photos for themselves to look back on.

“Not only do we find that most people take both types of photos in different situations, but that people also differ across situations in whether their goal for taking photo is to capture the physical experience of the moment or the bigger meaning of the moment in their life,” says lead author Zachary Niese, of the University of Tübingen.

Across six studies involving over 2,100 participants, researchers found that people are more likely to take third-person photos when their goal is to capture meaning, and that people are reminded more of the meaning when looking at their own third-person photos, compared to first-person. Researchers also found that people tend to like their photos more when the perspective matches their goal for taking the photo.

“Taking and posting pictures is a part of everyday life for many people. While there is sometimes derision about photo-taking practices in popular culture, personal photos have the potential to help people reconnect to their past experiences and build their self-narratives,” says Dr. Niese.

Dr. Niese warns against inferring that photos taken from one perspective are “better” than another. The research demonstrates that the most effective perspective depends on the person’s goal in the moment – whether that be to capture a physical experience or the deeper meaning of an event.

As people become more mindful of their goals when taking pictures and the role of perspective, they can become more skilled at preserving memories that they can reflect on later.

“People’s photo-taking practices have the potential to serve a more fundamental human motive to develop and understand our sense of self, both in terms of the experiences in our life as well as their bigger meaning,” says Dr. Niese.

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JOURNAL

Social Psychological and Personality Science

DOI

10.1177/19485506231163012 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Picturing Your Life: The Role of Imagery Perspective in Personal Photos

ARTICLE PUBLICATION DATE

27-Apr-2023

Why people include themselves in photos

Study finds some selfies help capture the meaning of an event

Peer-Reviewed Publication

OHIO STATE UNIVERSITY

COLUMBUS, Ohio – A new study may help explain why people choose to include themselves in some photos – and it is not vanity.

 

Researchers found that first-person photos (capturing the scene as it looks from one’s own eyes) best represent the physical experience of an event for people.

 

But third-person photos like selfies (documenting a moment with themselves in it) better depict the deeper meaning of the event in their lives.

 

“We found that people have a natural intuition about which perspective to take to capture what they want out of the photo,” said lead author Zachary Niese, a PhD graduate of The Ohio State University, now a postdoctoral scholar at the University of Tübingen in Germany.

 

The results also provide a counter to the view that people post selfies on sites like Instagram just to promote themselves, said study co-author Lisa Libby, professor of psychology at Ohio State.

 

“These photos with you in it can document the bigger meaning of a moment,” she said. “It doesn’t have to be vanity.”

 

The study was published today (April 27, 2023) in the journal Social Psychological and Personality Science.

 

Previous research suggested that capturing the physical experience of an event or its broader meaning may be two important motivations for taking personal photos.

 

For example, someone at the beach with a friend may take a photo of the ocean to capture the physical experience of the beautiful and relaxing day.  Or they could take a photo with themselves in it to capture the bigger meaning of spending time with a friend.

 

In a series of six studies involving 2,113 participants, the researchers explored the impact of perspective in personal photography.

 

In one online study, participants read a scenario in which they might want to take a photo, such as spending the day at a beach with a close friend.  They were asked to rate how important the experience itself would be for them, and how important the bigger meaning would be. Results showed that the higher participants rated the meaning of the event to them, the more likely they said they would take a photo with themselves in it.

 

Another study demonstrated the truth of people’s intuitions about whether each perspective better captures the experience or meaning of events. This study asked people to examine photos they posted to their Instagram accounts.

 

Participants opened their most recent post featuring their own photo and were asked: “What does this photo make you think about more?” with the response options being “The physical experience of the moment” or “The bigger meaning of the moment.”

 

Results showed that if the photo featured the participant in the shot, they were more likely to say the photo made them think of the bigger meaning of the moment, while photos featuring how the scene looked from their own visual perspective made them think of the physical experience.

 

But sometimes people may not take the photo that captures their goal – and the result is that they don’t like the photo as much.

 

In another experiment, the researchers again asked participants to open their most recent Instagram post featuring one of their photos.  They were asked whether they were trying to capture the bigger meaning or the physical experience of the moment.

 

Participants then rated how they felt about the photo on a scale of 1 (not at all positive) to 5 (extremely positive).

 

“We found that people didn’t like their photo as much if there was a mismatch between the photo perspective and their goal in taking the photo,” Libby said.

 

For example, if they said their goal was to capture the meaning of the moment, they liked the photo more if it was taken in third person, with themselves in the image.

 

Overall, the results suggest that people have an intuition about what perspective they should use in photos to fulfill what they want the photo to do, Niese said.

 

“I hope this study increases people’s knowledge about how photo perspective affects how they react to photos,” he said. “That way they can make sure they consciously choose the perspective that will meet their goal.”

 

The results also suggest people may be posting photos on Instagram and elsewhere for more than just their audience, Niese said.

 

“This work suggests people also have very personal motives for taking photos. Even on social media, it appears that people are curating images for themselves to look back on to capture the experience or the meaning of the event,” he said.

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JOURNAL

Social Psychological and Personality Science

DOI

10.1177/19485506231163012 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Picturing Your Life: The Role of Imagery Perspective in Personal Photos

ARTICLE PUBLICATION DATE

27-Apr-2023

Ant mounds are more important for biodiversity than previously thought

The ant mounds on the heath, in the forest and in your garden are oases for life. The heat and nutrients from ant mounds make them the perfect home for unique plant and animal species, according to new research.

Peer-Reviewed Publication

AARHUS UNIVERSITY

 

IMAGE: RIKKE REISNER HANSEN IS HAVING A REST ON THE HEATH IN HER HUNT FOR ANT MOUNDS TO EXAMINE. SHE'S A BIOLOGIST BY TRAINING OG STARTED HER CAREER IN GREENLAND WHERE SHE TRIED TO FIGURE OUT HOW CLIMATE CHANGE AFFECTS THE INSECTS. NOW SHE'S FOCUSED ON THE NATURE OF DANMARK AND ESPECIALLY THE DIFFERENT SPECIES OF ANTS. view more 

CREDIT: RIKKE REISNER HANSEN (PRIVATE PHOTO)

Most of us are annoyed by ants in our gardens. There are so many of them! And if you leave food out on your garden table, even for just a couple of minutes, the table will be swarming with ants when you return. 

Most garden owners will therefore do everything they can to get rid of ant colonies in their garden. But perhaps we should leave the ants be? Because they are hugely beneficial for biodiversity, a new study shows.

With colleagues from the Department of Ecoscience at Aarhus University, Rikke Reisner Hansen has studied ant mounds on Danish heathlands to discover their importance for other insects and for plants. And they really are important!

"The ants drag dead animals back to the ant mound, and this adds carbon and other important nutrients to the surrounding soil. The ant mound moreover warms up the surrounding ground, and in springtime, adders, lizards and beetles like to rest near ant mounds for warmth. The heat and the nutrients create unique conditions that allow certain plant species that don’t otherwise thrive on heathland to thrive on the ant mound," she says.

Went digging on the heath

Equipped with a spade, Rikke Reisner Hansen went to the heath to study the role of ant mounds in heathland wildlife. She looked for two types of ant mound: 

Those belonging to the narrow-headed ant, which look almost identical to the ant mounds you see in Danish forests. However, instead of pine needles, narrow-headed ants use leaves from heather and grass. And mounds belonging to the yellow meadow ant. This is a small ant that builds its nest from mineral soil on heathlands.

Whenever she came across an ant mound, she took out her spade and dug a deep hole right next to the ant mound. In this way, she could study how the ant mound affected the soil, roots and wildlife both above and below the mound. She also measured the temperature on top of the ant mound, and she examined the soil around and underneath it to determine the soil nutrients.

“It appears that the top part of the ant mound acts like a kind of miniature Costa del Sol for insects and reptiles. The animals exploit the excess heat from the ants for warmth in early spring and on chilly mornings," she explains, and continues:

“The same applies to plants. If a plant grows on an ant mound, it will blossom or come into leaf faster than the same species growing in the surrounding heathland soil. This is a huge benefit for insects that feed on pollen and nectar, because the ant mounds introduce an extra flowering season.

“When the worker ants discover what they mistakenly believe is a queen larva, they drag it into the ant nest. They feed the caterpillar, and sometimes they even forget their own offspring, and the colony dies."

Rikke Reisner Hansen

By digging holes next to the ant mounds Rikke Reisner Hansen was able to both see and measure how the mounds affects the soil around them. The thermometer showed that the temperature is slightly warmer next to the ant mound because the ants emit heat.

The butterfly that fooled an entire colony

The Alcon blue is a butterfly that lives only on the heathland where ants live. The caterpillar of the Alcon blue has developed a method by which it tricks the ants into thinking it is their queen.

“The Alcon blue lays its eggs on the rare marsh gentian plant. The caterpillar feeds on marsh gentian seeds during the first three stages of its life. When it has grown big enough, it falls to the ground and begins to emit a smell and a sound identical to those of a queen ant larva," says Rikke Reisner Hansen, and continues:

“When the worker ants discover what they mistakenly believe is a queen larva, they drag it into the ant nest. They feed the caterpillar, and sometimes they even forget their own offspring, and the colony dies." 

The caterpillar winters in the ant mound and, come spring, it spreads its beautiful blue wings and leaves the ant mound. Denmark is home to 12 species of gossamer-winged butterfly - the family of butterflies to which the Alcon blue belongs. Eleven of these species thrive best in places where ants also live. And a handful of these depend on ants to complete their life cycle.

But the ant mounds are also important for other species. Protecting ant mounds can therefore be an important step in mitigating the biodiversity crisis.

Important for biodiversity

The world, including Denmark, is in the middle of a biodiversity crisis. We are losing species at an ever-faster rate as we destroy important habitats when we fell forests, cultivate heathlands or drain bogs.

A total of 1,844 species of animal, plant and fungi are under threat of extinction in Denmark alone. Among these is the Alcon blue. In just 40 years, the Alcon blue has lost more than 15 per cent of its habitat in Denmark. This could be because of the way we manage our heathlands, Rikke Reisner Hansen explains.

"We tend to manage our heathlands as a homogenous landscape. We often apply the same management method throughout a heathland to preserve it as an open landscape. For example, we allow too many animals to graze the land. Or we use large machines to cut the vegetation. Unfortunately, this destroys the ant mounds.

To ensure many different plants and animals on the heath, we need to rewild the landscape, or at least return it to the way it was before machinery took over from traditional management systems,” she explains.

"It's all about creating a varied landscape. If you apply a varied management system, the result will be a varied landscape."

Rikke Reisner Hansen

This mound is made by the yellow meadow ant.

 

A changing landscape

Before humans began to shape and cultivate the land, most of Denmark was covered in forest. When a lightning bolt hit a tree, it might set off a massive forest fire. Such fires could clear large areas of land, and from the blackened tree stumps and ashes an open heathland landscape emerged and developed.

Slowly, over the course of decades, trees grew up again and eventually the forest returned. In this way, heathlands emerged and disappeared again over time throughout Denmark.

Because the heathlands were changing landscapes, they offered all kinds of habitat and were teeming with life. And an abundance of species! 

According to Rikke Reisner Hansen, this is the type of heathland landscape that must be restored in Denmark today if we want to do biodiversity good.

"We have to preserve the ant mounds and not use the same management method throughout the heath. Grazing and burning are important management techniques. But we have to apply methods varyingly and adjust them. If we allow goats, sheep or horses to graze on the same, restricted area throughout the summer, they will eat everything and leave a very homogeneous landscape, she says and explains further:

"It's all about creating a varied landscape. If you apply a varied management system, the result will be a varied landscape."

This is an ant mound made by the narrow-headed ant.

CREDIT

Rikke Reisner Hansen (private photo)

Leave the ant mounds be

In many places in Denmark, the local government is responsible for maintaining and managing the heathland landscapes. Therefore, since local governments often decide the vegetation management plans, maybe they should consider what Rikke Reisner Hansen has found out?

"Local governments have many skilled biologists in their workforce. They know it’s important to apply varied heathland management techniques. Unfortunately, it is often a matter of finances, and biodiversity is on the losing end,” she says.

But local governments are not the only ones who should listen to what Rikke Reisner Hansen has to say. Garden owners also need to change their game. At home, in her own garden, Rikke Reisner Hansen has been experimenting. She has left the ant mounds be. And this has led to much more life, she explains.

"After I left the ant mounds be and sowed wild, indigenous pea flowers, I now have many more common blue butterflies in my garden. It’s teeming with beautiful, blue butterflies,” she says.

She explains that it is not enough to plant a few meadow flowers here and there to create more biodiversity. It is important to think about the living conditions needed for the butterfly to complete its entire life cycle. Many insects need a variety of landscape types.

“For example, bees need areas with bare, solid soil. Small, warm spots where they can make nests. Other insects need small mounds of earth, water or deadwood. It’s also important to have plants that provide different types of nectar. Some bees can only use the nectar from a single or a few species of flower, and some butterflies only live on certain plants. It’s important that we ensure these small habitat variations in our gardens, both in terms of space and across the year, if we want to give diversity back to nature,” she concludes.

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JOURNAL

Arthropod-Plant Interactions

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Ant mounds extend the duration of plant phenology events and enhance flowering success

Impact of fall armyworm pest in Sub-Saharan Africa worsened by COVID-19, study reveals

The impact of the fall armyworm pest on maize crops and communities in Sub-Saharan Africa were worsened by the COVID-19 pandemic, according to new CABI-led research published as a Current Opinion article in the journal Environmental Sustainability.

Peer-Reviewed Publication

CABI

 

IMAGE: FALL ARMYWORM view more 

CREDIT: CABI

The impact of the fall armyworm pest on maize crops and communities in Sub-Saharan Africa were worsened by the COVID-19 pandemic, according to new CABI-led research published as a Current Opinion article in the journal Environmental Sustainability.

Drawing upon recent empirical literature on the pest since it was first reported in Africa in 2016, CABI scientists from its regional centre for Africa in Nairobi, Kenya, highlighted how it was responsible for up to 58% of maize losses worth up to US $9.4 billion.

The researchers confirm that the fall armyworm (Spodoptera frugiperda) remains an important pest in Africa’s farming systems and that more research and communication of low-cost options for sustainability are needed to manage it in the face of similar threats in the future.

The fall armyworm is arguably the most damaging invasive species to afflict all corners of the continent affecting major African crops – particularly maize, sorghum, millet and legumes.

Dr Monica Kansiime, lead author of the paper featured as part of the journal’s themed issue on emerging pests and pathogens, said the containment measures for COVID-19 created conditions for a major disruption to food system supply chains, giving rise to a dramatic increase in hunger.

The researchers highlight that, according to He and Krainer (2020), while 7.4 million people were infected by COVID-19 in 2020, up to 811 million people were undernourished, almost 10% of the world's population, most of whom are in Africa.

Hunger-related fatalities reached four million in 2020, 10 times the number of COVID-19 fatalities, the paper states.

Dr Kansiime said, “COVID-19 revealed how agricultural systems are extremely vulnerable to crises. This underscores the need for a recovery effort that focuses on building back better for smallholder communities to overcome the impacts of the pandemic, and build resilience against similar threats in the future.

“Institutional strengthening and smallholder linkages to input and output markets, and microcredit support, for instance, will address immediate production challenges in the wake of COVID-19.”

The researchers, which also included Dr Ivan Rwomushana and Idah Mugambi, reviewed the invasion and impact of fall armyworm on the livelihoods of smallholders in Sub-Saharan Africa and implications for community sustainability in the wake of COVID-19, drawing on a synthesis of peer-reviewed articles published between 2020 and 2022.

They highlight new lessons learned since the fall armyworm invasion in Africa in 2016 and make recommendations for policy and practice for sustainable management of this pest, as well as preparedness to manage future threats.

The scientists point out that since the declaration of COVID-19 as a global pandemic in January 2020, there has been a massive disruption of livelihoods due to the disease itself but also exacerbated by stringent measures put in place to try and curb the spread of the disease.

Agricultural workers in low- and middle-income countries that have labour-intensive farming systems suffered disruptions in their supply chains and outputs were compromised due to labour shortages, they stress.

Disruptions in the supply and availability of critical production inputs such as fertilizers, plant protection products, and seeds were apparent. This contributed to limited crop protection interventions by farmers, including monitoring for the pest, weeding, and timely pesticide sprays, which have direct effects on both preventive and curative pest management actions, the researchers argue.

Ms Mugambi said, “Enhancing the technical capacities of smallholders to use Integrated Pest Management measures, and regional collaboration for multi-risk monitoring and early warning will inform prevention, preparedness, and coordinated actions for the sustainable management of emerging risks in the future.”

 

Additional information

Main image: The impacts of the fall armyworm in Sub-Saharan Africa were worsened by COVID-19 due to distractions in supply chains (Credit: CABI).

Full paper reference

Monica K Kansiime, Ivan Rwomushana, Idah Mugambi, ‘Fall armyworm invasion in Sub-Saharan Africa and impacts on community sustainability in the wake of Coronavirus Disease 2019: reviewing the evidence,’ Current Opinion in Environmental Sustainability, Volume 62, 2023, 101279, ISSN 1877-3435, DOI: 10.1016/j.cosust.2023.101279.

You can read the paper open access in full here: https://www.sciencedirect.com/science/article/pii/S187734352300026X

Funding acknowledgement

The study was funded under CABI’s PlantwisePlus program. CABI is an international intergovernmental organization and we gratefully acknowledge the core financial support from our member countries (and lead agencies) including the United Kingdom Foreign, Commonwealth, and Development Office (FDCO), European Union, China (Chinese Ministry of Agriculture), Australia (Australian Centre for International Agricultural Research), Canada (Agriculture and Agri-Food Canada), Netherlands (Directorate-General for International Cooperation-DGIS), Switzerland (Swiss Agency for Development and Cooperation) and Ireland (Irish Aid, International Fund for Agricultural Development-IFAD). See https://www.cabi.org/about -cabi/who-we-work-with/key-donors/ for details.

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JOURNAL

Environmental Sustainability

DOI

10.1016/j.cosust.2023.101279 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Fall armyworm invasion in Sub-Saharan Africa and impacts on community sustainability in the wake of Coronavirus Disease 2019: reviewing the evidence

The reasons why insect numbers are decreasing

A researcher from Mainz University has published a special issue of Biology Letters on the causes and consequences of the worldwide insect decline as well as potential countermeasures

Peer-Reviewed Publication

JOHANNES GUTENBERG UNIVERSITAET MAINZ

 

IMAGE: THE DARK BUSH-CRICKET PHOLIDOPTERA GRISEOAPTERA IS ONE OF THE MANY DECLINING INSECT SPECIES IN CENTRAL EUROPE. view more 

CREDIT: PHOTO/©: BEAT WERMELINGER

The reasons why insect numbers are decreasing

A researcher from Mainz University has published a special issue of Biology Letters on the causes and consequences of the worldwide insect decline as well as potential countermeasures

Throughout the world we are witnessing not just a decline in the numbers of individual insects, but also a collapse of insect diversity. Major causes of this worrying trend are land-use intensification in the form of greater utilization for agriculture and building development as well as climate change and the spread of invasive animal species as a result of human trade. These are the main conclusions reached in the special feature on insect decline that recently appeared in Biology Letters. One of the three editors is PD Dr. Florian Menzel from the Institute of Organismic and Molecular Evolution at Johannes Gutenberg University Mainz (JGU). "As evidence of an on-going global crash in insect populations increased over the last few years, we decided it was time to edit and publish this special issue. Our aim was not to document insect population declines but to better understand their causes and consequences," said Menzel. Together with forest entomologist Professor Martin Gossner of the Swiss Federal Institute for Forest, Snow and Landscape Research (WSL) and biologist Dr. Nadja Simons of TU Darmstadt, Menzel contacted international researchers in order to collate the information they could provide on insect declines and to stimulate new studies on the subject. The special issue authored by Menzel, Gossner and Simons includes 12 research-related articles, two opinion papers, and an extensive editorial.

More extensive use of land, climate change, and invasive species are the main causes of insect decline

"In view of the results available to us, we learned that not just land-use intensification, global warming, and the escalating dispersal of invasive species are the main drivers of the global disappearance of insects, but also that these drivers interact with each other," added Menzel. For example, ecosystems deteriorated by humans are more susceptible to climate change and so are their insect communities. Added to this, invasive species can establish easier in habitats damaged by human land-use and displace the native species. Hence, while many insect species decline or go extinct, few others, including invasive species, thrive and increase. This leads to an increasing homogenization of the insect communities across habitats.

"It looks as if it is the specialized insect species that suffer most, while the more generalized species tend to survive. This is why we are now finding more insects capable of living nearly anywhere while those species that need specific habitats are on the wane," Menzel pointed out. The consequences of this development are numerous and generally detrimental for the ecosystems. For example, the loss of bumblebee diversity has resulted in a concomitant decline in plants that rely on certain bumblebee species for pollination. "Generally speaking, a decline in insect diversity threatens the stability of ecosystems. Fewer species means that there are fewer insects capable of pollinating plants and keeping pests in check. And, of course, this also means that there is less food available for insect-eating birds and other animals. Their continued existence can thus be placed at risk due to the decline in insect numbers," emphasized Menzel.

In their editorial, Menzel, Gossner, and Simons suggest ways in which we can best respond to the effects that their gathered data has revealed. They advocate a particular approach for future research into insect decline. Standardized techniques should be employed to monitor insect diversity across many habitats and countries, the more so as in many regions of the world we still don't know how the insects are doing. The researchers also propose the creation of a network of interconnected nature reserves such that species can move from one habitat to another. Less heat-tolerant insects would thus be able to migrate from areas where global warming is causing temperatures to rise to higher elevations or cooler regions in the north. Furthermore, we need measures to reduce the dispersal of invasive animal and plant species through our globalized trade and tourism. "This is another problem that has become extremely serious in the last decades," concluded Menzel. One example cited in the current special issue is the invasion of non-native insectivorous fishes in Brazil that has caused a major decline in freshwater insects.

A common red ant (Myrmica rubra) worker carrying a seed of the hollowroot plant (Corydalis cava). The dispersal of seeds is one the many positive effects that ants have in ecosystems.

CREDIT

photo/©: Philipp Hönle

JOURNAL

Biology Letters

DOI

10.1098/rsbl.2023.0007 

METHOD OF RESEARCH

Commentary/editorial

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Less overall, but more of the same: drivers of insect population trends lead to community homogenization

Arthropods in high-diversity forests contribute to improved productivity

Peer-Reviewed Publication

CHINESE ACADEMY OF SCIENCES HEADQUARTERS

 

IMAGE: BEF-CHINA EXPERIMENT SITES, HERBIVOROUS CATERPILLARS FEEDING ON TREE LEAVES, AND A PREDATOR WASP PREDATING LEAF-MINING CATERPILLAR view more 

CREDIT: LI SHAN, ANDREAS SCHULDT AND CHEN HUAYAN

An international team of researchers led by Prof. MA Keping from the Institute of Botany of the Chinese Academy of Sciences (IBCAS) has shown that forests with higher tree species richness tend to have greater arthropod diversity.

The researchers showed that higher tree diversity promotes productivity through the suppression of herbivores by enemy arthropods.

These findings, published recently in Nature Ecology & Evolution, underscore the importance of arthropod diversity as a mediator of the effects of tree diversity on forest productivity.

Managing forests for increased productivity will require both increased tree diversity and multitrophic diversity, according to the researchers.

Forests are home to 80% of terrestrial plant and animal diversity, making them a critical component of global biodiversity conservation. However, forest biodiversity is under serious threat from anthropogenic disturbance and climate change. Species-rich groups such as arthropods are declining dramatically due to the degradation of forests and loss of plant diversity.

Most studies of biodiversity–ecosystem functioning (BEF) relationships have focused solely on plant diversity, neglecting the impact of the diversity of other trophic groups. As a result, it remains unclear how the diversity of herbivores and their enemies affects ecosystem functioning. Given the importance of forests in providing essential ecosystem services and global biodiversity, it is vital to understand these relationships and take action to protect them.

Using five years of data on aboveground herbivorous, predatory, and parasitoid arthropods, together with tree growth data from a large-scale forest biodiversity experiment in southeastern China (BEF-China), the researchers showed that the effects of increased tree species richness were consistently positive for species richness and abundance of herbivores, predators, and parasitoids.

This finding is consistent with a previous study from another large grassland biodiversity experiment (the Jena Experiment) and again shows that conserving plant diversity is important to conserving arthropod diversity.

However, in contrast to the bottom-up control of arthropod diversity by plant diversity in the central European grassland study, this new study in the species-rich forests of southeastern China shows that higher tree diversity can enhance the top-down control of herbivores by their enemies, thereby contributing to increased productivity.

"This study emphasizes that arthropod diversity plays an important role in mediating the effects of tree diversity on primary productivity," said Dr. LI Yi, a postdoc researcher at IBCAS and first author of the study.

A previous study conducted at the same sites showed that increasing plant diversity can promote forest productivity directly. The new study shows that increasing plant diversity can also indirectly increase forest productivity by promoting arthropod diversity and trophic interactions.

"It underscores the critical role of conservation efforts aimed at maintaining forest biodiversity," said Prof. LIU Xiaojuan, senior author and leader of the BEF-China management group.

To draw more reliable conclusions, the researchers conducted multi-year sampling. According to Prof. MA, chairman of the BEF-China platform, this approach takes into account the possibility that different arthropod groups may be affected inconsistently from year to year.

"It also highlights the value of the BEF-China platform, not only as the world’s largest experiment on forest biodiversity and ecosystem functioning, but also as an open and international platform for long-term ecological research," he said.

"The BEF-China platform provides valuable opportunities for international research teams and young researchers in different directions," said Prof. ZHU Chaodong, an author from the Institute of Zoology of CAS.

Overall, while several recent studies have documented declines in terrestrial arthropod biodiversity, few have examined the consequences for ecosystems.

"This work fills that gap by demonstrating the important role of arthropod diversity in BEF relationships," said Prof. Bernhard Schmid, an author from the University of Zurich.

In summary, these findings are of great importance in guiding the public to understand the conservation of forest biodiversity, plants, animals, and ultimately their associated microbes.

Relationships between tree diversity and species richness of herbivores (a), predators (b), parasitoids (c) and multitrophic groups (d)

Relationships between species richness of predators (a), parasitoids (b), multitrophic groups (c) and productivity; direct and indirect effects of tree species richness, functional traits, and overall arthropod (d) or herbivore and enemy (e) species richness on productivity

CREDIT

IBCAS

JOURNAL

Nature Ecology & Evolution

DOI

10.1038/s41559-023-02049-1 

METHOD OF RESEARCH

Meta-analysis

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Multitrophic arthropod diversity mediates tree diversity effects on primary productivity

ARTICLE PUBLICATION DATE

27-Apr-2023

When employees leave their jobs, coworkers call it quits: UBC study

Peer-Reviewed Publication

UNIVERSITY OF BRITISH COLUMBIA

People leave jobs all the time, whether they’re laid off, fired, or just quit. But how do their departures affect coworkers left behind? According to a new study from the UBC Sauder School of Business, those exits can lead many others to call it quits.  

The researchers delved deeply into employment data from a major retailer that was experiencing high turnover to find out why. They reviewed data for roughly a million employees — including when they were hired, which store, which position, when they left, and why. 

The study authors also had access to employee performance records, so they could evaluate whether workers were high performers or low performers. 

“We looked at these stores as systems, and looked at the flow of employees in and out of them over time,” explained UBC Sauder assistant professor Sima Sajjadiani (she/her), who co-authored the study with John Kammeyer-Mueller and Alan Benson of the University of Minnesota. “It gave us a great opportunity to look at the immediate, short-term and long-term effects of each exit event, and compare them over time.”

Past studies have looked at how turnover affects remaining employees, but they typically focus on employee performance after others leave — and on the performance of the company overall. The UBC study is the first of its kind to look at the extent to which employee exits lead to even more departures, what types of exits cause the most churn, and the role that the performance level of exiting employees plays.  

The researchers found that layoff announcements have a strong and immediate effect, and boost voluntary turnover among those who survive the layoffs. 

“It’s very bad news for organizations, especially if they are laying off high performers, because if those positions get eliminated, both high and low performers start quitting,” said Dr. Sajjadiani.  “It’s a signal that people’s jobs aren’t secure, and the organization doesn’t care about them, no matter how hard they work. So they think, ‘I should leave as soon as possible.’”

When employees quit their jobs voluntarily, their departures give a more moderate boost to voluntary turnover, and it takes longer for that ripple effect to occur. 

“To high performers, voluntary exits are a positive signal that there are better opportunities elsewhere,” said Dr. Sajjadiani. “So while employees might not leave immediately, they do begin to look for other opportunities.”

When workers are dismissed, however, their departures have a relatively small and fleeting effect — and can even reduce voluntary turnover. 

“Usually these are people who are disruptive or abusive, or aren’t doing their fair share,” said Dr. Sajjadiani. “When they go, high performers tend to stay longer, and the risk of voluntary turnover actually goes down.”

However, when a high performer is dismissed without clear justification, employers not only open themselves to legal headaches, it also sends the wrong message to other high performers. They also start heading for the door. 

According to Dr. Sajjadiani, organizations vastly underestimate the ripple effects of people leaving and the resulting human capital costs. The research also sends a clear message to organizations that they should be extremely careful when they make exit decisions, or they risk destabilizing the whole organization very quickly. 

“Communicating clearly and compassionately, justifying these decisions and trying to avoid the most severe course of actions are better for organizations than simply cutting people,” Dr. Sajjadiani said. 

Interview language: English

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JOURNAL

Academy of Management Journal

DOI

10.5465/amj.2021.1327 

ARTICLE TITLE

Who Is Leaving and Why? The Dynamics of High-Quality Human Capital Outflows