Galactic panspermia: How far could life spread naturally in a galaxy like the Milky Way?

by Evan Gough, Universe Today

Here it is, the simulated galaxy called g15784. Two spheroidal galaxies are seen in the

 image, one above the galactic plane and one below. Credit: Gobat et al 2021.

Can life spread throughout a galaxy like the Milky Way without technological intervention? That question is largely unanswered. A new study is taking a swing at that question by using a simulated galaxy that's similar to the Milky Way. Then they investigated that model to see how organic compounds might move between its star systems.

The central question in science is probably "How did life begin?" There's no larger question, and there's no answer, so far. A secondary question is more approachable: "Can life spread from star to star?" That's the theory of panspermia, in a nutshell.

Earth's history poses an important question when it comes to panspermia. Scientists think there wasn't enough time between when the Earth cooled enough to become habitable and the appearance of life. Not all scientists think that, of course. There's a range of thoughts on the matter. But the question remains: Was there enough time for DNA-based life to get going independently on Earth, or did panspermia play a role?

While much of the talk around panspermia concerns simple lifeforms somehow moving between stars, more serious talk concerns the movement of organic compounds necessary for life. Scientists have found some of those compounds on comets and elsewhere out in space. We now know they're not necessarily rare. So can those compounds move around from solar system to solar system?

The new study is titled "Panspermia in a Milky Way-like Galaxy." The lead author is Raphael Gobat, from Instituto de Física, Valparaíso, Chile. The paper is available on the pre-print site arxiv.org.

So is panspermia a thing? Inside a solar system like ours, it seems possible. Meteorites from Mars have landed on Earth, which is pretty solid evidence. If rocks can make the trip, why not chemicals in or on those rocks? Could spores make the interstellar trip between star systems?

The team of researchers set out to answer that question. They worked with a simulated galaxy from MUGS, the McMaster Unbiased Galaxy Simulations. MUGS is a set of 16 simulated galaxies created by researchers in the early 2000s. In 2016, Gobat et al added a modified galactic habitability model, called GH16.

Credit: Universe Today

Their chosen galaxy is g15784. It's a little more massive than the Milky Way and has a history of quiescent mergers. It hasn't merged with anything very massive in a long time, and it's orbited by several spherical galaxies.

The team computed a level of habitability for each star particle in the galaxy. In this case, that means the number of main sequence low-mass stars with terrestrial planets within their habitable zones. They followed GH16 to do that. GH16 takes into account stellar metallicity, minimum and maximum mass, formation history, and the inner and outer ranges of its habitability zone (HZ.)

They also considered the effect of supernovae explosions on habitability. The galactic core is the most densely populated part of the galaxy. So even though there are more potentially habitable planets there, there are also more deadly supernovae. The higher density of stars in the core means each habitable planet has a higher chance of being rendered uninhabitable by a supernova. The higher metallicity in the core also reduces habitability, according to the authors. That makes the central region a tough place for panspermia.

The group also looked at the spiral arms of g15784. While star density is also high there, and so are supernova rates (SNR), they didn't affect habitability the same as in the bulge. They also looked at the galactic disk and halo.

The study shows that panspermia is at least possible, though there's no simple answer to the question. They found that while median habitability increases with galactocentric radius, while the probability for panspermia is inverse. That's because of the higher star density in the galactic bulge.

But panspermia probability is low in the central disk. That's because of higher supernova rates and a lower escape fraction due to higher metallicity. Natural habitability doesn't vary much throughout the galaxy, whereas panspermia probability varies widely, by several orders of magnitude.

The team found no correlation between the probability of panspermia and the habitability of the receiving particle. (In this study, particle refers to a high number of stars, due to the simulation's low resolution.)

A three-panel figure from the paper showing a projected column at z = 0 and in a

 1 kpc-wide slice passing through the center of g15784. The top shows the median value

 for natural habitability, the middle shows the fraction of possible cradles in the simulated galaxy, and the bottom shows the fraction of possible colonization targets. The magenta star shows where the sun would be if this were the Milky Way. Image Credit: Gobat et al 2021.

Lastly, they found that panspermia is less effective than in-situ prebiotic evolution, although they say that they can't quantify that precisely.

In their conclusion, the authors point out several caveats for the work. "… first, it includes several factors that we have regarded as unknown constants (e.g., the capture fraction of spores by target planets, the relation between habitability and the presence of life, the typical speed of interstellar objects, and the absolute value of escape fraction of the interstellar organic compounds from source planets)." As a result, they consider their results to be "… naturally more qualitative than quantitative."

They also caution that while a real galaxy like the Milky way is dynamic and changing, their simulated galaxy is just a snapshot. "As such, these results only apply if the typical timescale for panspermia is much shorter than the dynamical timescale of a galaxy."

There are other differences between the simulated galaxy and the Milky Way. "For example, our mock galaxy has a larger value of bulge-to-disk light ratio than the actual Milky Way, and the galactic bulge has been suggested to be well-suited for panspermia." Finally, they point out that MUGS is a low-resolution simulation, and a higher-resolution simulation could produce some differences in the results.

We've recently been visited by two interstellar objects: "Oumuamua and comet 2L/Borisov. So we know that objects are traveling between star systems. There've probably been many more interstellar visitors that we weren't technologically capable of seeing. And we know that organic building blocks are present out in space.

That doesn't prove that organic building blocks can travel between stars, but it seems possible. Thanks to this research, we might know a little more about how likely it is, and where in a galaxy it might take place.Cold planets exist throughout the galaxy, even in the galactic bulge

More information: Raphael Gobat et al, Panspermia in a Milky Way-like Galaxy. arXiv:2109.08926v1 [astro-ph.GA], arxiv.org/abs/2109.08926

Source Universe Today 

Butterflies and moths evolve in order to adapt to warmer urban areas

by Bob Yirka , Phys.org

Latticed heath moth (Chiasmia clathrata) in an urban environment. Credit: Sami M. Kivelä.

A team of researchers affiliated with several institutions in Finland, Belgium and Sweden, has found that some butterflies and moths have evolved to suit the warmer conditions they find in urban areas. In their paper published inof the National Academy of Sciences, the group describes their study of data obtained from citizen-science observation databases and standardized monitoring efforts regarding butterfly and moth flight seasons.

Prior efforts have shown that urban environments have slightly different weather and seasonality than the areas that surround them. This is because urban material absorbs heat and more light is produced. In the new effort, the researchers wondered what impact living in cities might be having on butterflies and moths. To find out, they first obtained access to multiple databases containing information about two specific species—Pieris napi and Chiasmia clathrate—along with standardized monitoring effort results and analyzed what they found in them.

The researchers found that both species were flying around in their city environments a few weeks earlier than samples of the same species in neighboring rural areas. The data also showed that it was not likely that the lights of the city were responsible for the change; it was the higher temperatures. To find out if the behavior was learned or if it had evolved in the species, the researchers captured multiple specimens from both urban and rural locations and allowed them to grow in their lab. In the lab, all of the specimens lived under the same heat and lighting conditions, but those collected from urban areas still matured earlier, showing that the insects have evolved to suit the warmer conditions found in cities. The researchers note that maturing earlier can give city butterflies and moths an advantage by allowing them to reproduce more than once in a given season. They further suggest that the higher temperatures in the city also explain why both species can be seen later in the year than those out in the country; the warmer temperatures allow the second set of caterpillars time to mature before the cold temperatures arrive.Study shows link between urbanization and changes in body size of animals

More information: Thomas Merckx et al, Urbanization extends flight phenology and leads to local adaptation of seasonal plasticity in Lepidoptera, Proceedings of the National Academy of Sciences (2021). DOI: 10.1073/pnas.2106006118

Journal information: Proceedings of the National Academy of Sciences 

© 2021 Science X Network

Our climate projections for 2500 show an Earth that is alien to humans

by Christopher Lyon Et Al, The Conversation

Current climate future predictions do not go far enough. Credit: Shutterstock

There are many reports based on scientific research that talk about the long-term impacts of climate change—such as rising levels of greenhouse gases, temperatures and sea levels—by the year 2100. The Paris Agreement, for example, requires us to limit warming to under 2.0 degrees Celsius above pre-industrial levels by the end of the century.

Every few years since 1990, we have evaluated our progress through the Intergovernmental Panel on Climate Change's (IPCC) scientific assessment reports and related special reports. IPCC reports assess existing research to show us where we are and what we need to do before 2100 to meet our goals, and what could happen if we don't.

The recently published United Nations assessment of Nationally Determined Contributions (NDCs) warns that current promises from governments set us up for a very dangerous 2.7 degrees Celsius warming by 2100: this means unprecedented fires, storms, droughts, floods and heat, and profound land and aquatic ecosystem change.

While some climate projections do look past 2100, these longer-term projections aren't being factored into mainstream climate adaptation and environmental decision-making today. This is surprising because people born now will only be in their 70s by 2100. What will the world look like for their children and grandchildren?

To grasp, plan for and communicate the full spatial and temporal scope of climate impacts under any scenario, even those meeting the Paris Agreement, researchers and policymakers must look well beyond the 2100 horizon.

Global mean near-surface air temperature (solid lines) and thermosteric sea level rise 

(dotted lines) anomalies relative to the 2000-19 mean for the RCP6.0, RCP4.5 and 

RCP2.6 scenarios. Shaded regions highlight the time horizons of interest and their

 nominal reference years. The bottom panel shows spatial anomalies relative to 

2000-19 mean for the 2100, 2200 and 2500 climates under the three RCPs.

 Credit: Lyon et al., 2021

After 2100

In 2100, will the climate stop warming? If not, what does this mean for humans now and in the future? In our recent open-access article in Global Change Biology, we begin to answer these questions.

We ran global climate model projections based on Representative Concentration Pathways (RCP), which are "time-dependent projections of atmospheric greenhouse gas (GHG) concentrations." Our projections modeled low (RCP6.0), medium (RCP4.5) and high mitigation scenarios (RCP2.6, which corresponds to the "well-below 2 degrees Celsius" Paris Agreement goal) up to the year 2500.

We also modeled vegetation distribution, heat stress and growing conditions for our current major crop plants, to get a sense of the kind of environmental challenges today's children and their descendants might have to adapt to from the 22nd century onward.

The Amazon: The top image shows a traditional pre-contact Indigenous village (1500 CE) 

with access to the river and crops planted in the rainforest. The middle image is a 

present-day landscape. The bottom image, considers the year 2500 and shows a

 barren landscape and low water level resulting from vegetation decline, with sparse or

 degraded infrastructure and minimal human activity. Credit: Lyon et al., 2021,

 CC BY-ND

In our model, we found that global average temperatures keep increasing beyond 2100 under RCP4.5 and 6.0. Under those scenarios, vegetation and the best crop-growing areas move towards the poles, and the area suitable for some crops is reduced. Places with long histories of cultural and ecosystem richness, like the Amazon Basin, may become barren.

Further, we found heat stress may reach fatal levels for humans in tropical regions which are currently highly populated. Such areas might become uninhabitable. Even under high-mitigation scenarios, we found that sea level keeps rising due to expanding and mixing water in warming oceans.

Although our findings are based on one climate model, they fall within the range of projections from others, and help to reveal the potential magnitude of climate upheaval on longer time scales.

Midwest U.S.: The top painting is based on pre-colonisation Indigenous cities and 

communities with buildings and a diverse maize-based agriculture. The second is the

 same area today, with a grain monoculture and large harvesters. The last image,

 however, shows agricultural adaptation to a hot and humid subtropical climate, 

with imagined subtropical agroforestry based on oil palms and arid zone succulents. 

The crops are tended by AI drones, with a reduced human presence. 

Credit: Lyon et al., 2021, CC BY-ND

To really portray what a low-mitigation/high-heat world could look like compared to what we've experienced until now, we used our projections and diverse research expertise to inform a series of nine paintings covering a thousand years (1500, 2020, and 2500 CE) in three major regional landscapes (the Amazon, the Midwest United States and the Indian subcontinent). The images for the year 2500 center on the RCP6.0 projections, and include slightly advanced but recognizable versions of today's technologies.

The Indian subcontinent: The top image is a busy agrarian village scene of rice planting, 

livestock use and social life. The second is a present-day scene showing the mix of

 traditional rice farming and modern infrastructure present in many areas of the 

Global South. The bottom image shows a future of heat-adaptive technologies including

 robotic agriculture and green buildings with minimal human presence due to the need for 

personal protective equipment. Credit: Lyon et al., 2021, CC BY-ND

Between 1500 and today, we have witnessed colonization and the Industrial Revolution, the birth of modern states, identities and institutions, the mass combustion of fossil fuels and the associated rise in global temperatures. If we fail to halt climate warming, the next 500 years and beyond will change the Earth in ways that challenge our ability to maintain many essentials for survival—particularly in the historically and geographically rooted cultures that give us meaning and identity.

The Earth of our high-end projections is alien to humans. The choice we face is to urgently reduce emissions, while continuing to adapt to the warming we cannot escape as a result of emissions up to now, or begin to consider life on an Earth very different to this oneIPCC says limiting any global warming is what matters most

Journal information: Global Change Biology

Provided by The Conversation 

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Urgent action must be taken to save the critically endangered Sumatran rhino

by Sunarto, The Conversation

Andatu, one of the Sumatran rhinoceros individuals born at semi-natural breeding facility

 in the Sumatran Rhino Sanctuary. Credit: Sunarto

Indonesia manage to conserve two of the world's five rhinoceros species. Both the Javan rhino (Rhinoceros sondaicus) and the Sumatran rhino (Dicerorhinus sumatrensis) still exist today, uniquely only in the country.

However, there are still challenges to overcome.

The population of the two rhino species are extremely small: each has fewer than 80 individuals. According to the International Union for Conservation of Nature (IUCN) Red List of threatened species, both are now classified as "Critically Endangered"—only one category away from being classed as "Extinct in the Wild."

The conservation efforts of the Javan rhinos have showed positive results in recent years. The population in Ujung Kulon National Park in southwestern Java has grown to 75 individuals.

Conservation efforts of the Sumatran rhino, on the other hand, have faced their own set of challenges.

Based on more than a decade of my experience to support monitoring, protection, and policy-making, as well as extensive communication with activists in the field, here I will explain the Sumatran rhinoceros' unique conditions. I will then highlight urgent actions needed to save them.

An ancient species in the modern era

The Sumatran rhino was once common across Asia, but its population worldwide has decreased by 80% in just three decades.

Recent assessment by the IUCN stated that the overall number of Sumatran rhinos is no more than 80 individuals—only 30 among them are adults. These individuals are dispersed throughout Aceh, Lampung, and Kalimantan.

It is not an easy task to save the Sumatran rhinos, but it is not impossible either. Over time, challenges continued to arise due to their not only shrinking but also scattered population.

Rhinos are herbivores that feed on leaves, buds, and twigs. They consume hundreds of different plants. In the rain forest habitat, rhinos feed on lower stratum plants such as the ginger family (Zingiberaceae), seedlings or young trees from the myrtle family (Myrtaceae), and even Gluta plants (Gluta spp.) that cause rashes when eaten by humans.

Rhinos also often roam in forest gaps, such as those that have been cleared due to fallen trees where regrowth takes place. Rhinos can look for food in the edge of forests, where a lot of seedlings, herbaceous plants, and other food are easily accessible. In order to sustain their lifestyle, rhinos require a diverse range of habitats, including sites for wallowing.

When the world's forests were still intact and human disturbance was still rare, Sumatran rhinos could easily and safely explore, obtain, and enjoy their food and interact with one another.

However, within the last few decades, human activities have increased dramatically.

Extractive industries and large-scale plantations transformed the landscape of Sumatra. As a result, the Sumatran rhino's populations were driven to the corners of their forests—often fragmented and isolated.

In addition to the need for food, rhinos also need habitats that allow them to wallow. 

Credit: Sunarto

As time went by, poaching activities also intensified with various hunting tools. Rhinos became one of the main targets.

Eventually, these rhinos lived an isolated life from one another, while their population continued to decrease.

The rhinos then experienced a phenomenon known as the Allee Effect. This phenomenon begins with the decline in the animal population in a certain area, which then leads to a decrease in their ability to reproduce.

Imagine if this happened to humans, and our species consisted of only 100 surviving individuals, split into five groups on two islands—thousands of kilometers apart. Individual interaction, let alone finding a companion, will be challenging.

This is the Sumatran rhino's main vulnerability today.

Under these circumstances, poaching bans and habitat protection will not be enough to prevent extinction. Critical situations like these can only be alleviated by increasing the birth rate of rhinos.

However, at the same time, the Sumatran rhinos are becoming more fragile due to their peculiar physiology and mating behavior.

Female Sumatran rhinos have only one reproductive cycle every 18–24 days, while the fertility window only lasts 24 to 48 hours. Encounters that occur outside that time window will be futile, and would not produce offspring.

Even if a meeting does take place at the right moment, it may not develop into a meaningful union between the rhinos. This double-horned species has a certain kind of aggressive ritual perhaps to assess the worthiness of a potential mate before reproducing. Partner incompatibility can cause the mating process to fail.

To make matters more complicated, the rhino's shrinking population also increase the risk of inbreeding. This can lead to a variety of undesirable consequences, such as certain illnesses and overall declining fitness.

Unpartnered adult female individuals are at further risk of pathological disorders in their reproductive organs. This can lead to infertility.

Because of these phenomena, slowly but surely the Sumatran rhinos have and likely can continue disappear from their habitats.

The rhino, which had previously endured for possibly millions of years, vanished throughout Peninsular Malaysia, Kerinci Seblat National Park, and Sabah in just 20 years.

Recently, there have been reported signs of rhino extirpation in a number of sites, including Bukit Barisan Selatan and even Way Kambas in Lampung, Sumatra. These reports have not included population conditions in smaller patches in Aceh.

Rhino horns are sought by hunters and poachers. Credit: Sunarto

Urgent rescue strategy needed

Three years ago, the government issued an Emergency Action Plan (Rencana Aksi Darurat or RAD) for the Rescue of Sumatran Rhinos.

The plan consists of various strategies for the population recovery, including rescuing rhinos from the wild.

The targeted rhinos are rescued and brought to the Sumatran Rhino Sanctuary—a semi-natural breeding facility. This step was taken to increase the number of rhinos available for semi-natural reproduction, and also assisted breeding through the help of technology.

Before the national rescue plan, there were successful captive breeding efforts, such as those taking place in the Way Kambas facility. With collaboration from the Indonesia government and The Rhino Foundation of Indonesia, two rhino calves named Andatu and Delilah were born in 2012 and 2016. Both have been carefully cared for and are growing healthily to this day.

Besides Way Kambas, there are also another facility built in West Kutai, East Kalimantan. The government plans to develop more of these facilities in Aceh.

These rescue efforts aim to increase the available rhino stock for breeding, as there are now only seven in the Way Kambas facility—with only one pair among them possessing the ability to generate offsprings—and one individual without any mates in West Kutai.

Meanwhile, major initiatives to safeguard rhinos from poaching continue to be part of the national rescue plan as a supporting program.

The implementation of the rescue plan, which has unfortunately been hampered by the pandemic, must be accelerated and regularly evaluated to adapt to new research findings, experiences, and discoveries from the field.

For instance, the conservation strategy in Bukit Barisan National Park or Way Kambas National Park should be updated, because there is new evidence that the rhino population has recently declined and even vanished. When the national rescue plan was put together, the two areas were thought to still have a large number of rhinos.

A recent study also provides valuable insight: most rhinos taken from isolated populations (more than 70%) tend to have pathological disorders in their reproductive organs, such as tumors and cysts that prevent them from conceiving.

Such individuals can actually still contribute to breeding efforts, but require the help of assisted reproductive technology—ART by harvesting gametes or egg cells to produce embryos.

Efforts to search for rhinos eligible for semi-natural breeding should therefore be concentrated on fertile and healthy individuals. These individuals are most probably only available in vast and robust populations—other individuals rescues from isolated areas who are likely to have reproductive problems, need to be supported by ART.

The government need to work in all areas to strengthen conservation strategy: leading the way for rescue efforts, promoting collaboration, and encouraging the involvement of communities and strategic partners.

It is a daunting task, but the recipe, resources and experience for a successful mission are available. It requires the government's adaptive leadership and teamwork with synergy of all parties to accelerate Sumatran rhino recovery.Critically endangered Sumatran rhino pregnant: conservationists

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Mali's elephants show how people and nature can share space in a complex world

by Susan Canney, The Conversation

The challenge of conserving wildlife while meeting the many needs of humans is a complex one. Some policymakers don't see how economies can grow while still making space for wildlife. Others understand that conservation must make space for people, but it's difficult to do in practice.

The issues involved in the coexistence of humans and wildlife are interconnected and can't be broken down into small, predictable, manageable parts.

Recognizing the uncertainty that arises from multiple relationships could help to make conservation more effective.

An example is provided by the "desert-adapted" elephants of Mali. These 250 to 300 animals are among the last of an elephant population that once stretched across the Sahel. They're now reduced to tiny refuges due to the intrusion of human activities.

The Mali elephants have been excluded, since the 1970s, from the rich resources of the inner delta by increasing human pressure. And their numbers have almost been halved by the poaching that accompanied the lawlessness of the 2012 coup. These animals have adapted by migrating annually over a vast, arid area to follow the availability of water and food, and to avoid human activity.

Our work as the Mali Elephant Project began with three years (2003–2006) of studying the elephants and their migration to understand the threats. We did this using GPS collar data provided by Save the Elephants. But it was difficult to see how a small organization with no resources could intervene over such a large area (about 32,000 km2) which was inhabited by people.

A better understanding of local attitudes and livelihoods helped us see the problem as part of a complex social-ecological system. In turn, that suggested ways to promote sustainable change. The results have continued to surprise. And the insights gleaned may be of use in delivering the Post-2020 Global Biodiversity Framework and supporting the achievement of the Sustainable Development Goals.

Developing the intervention model

Our work understood the threat to elephants to be as a result of a system of relationships between people and their living and non-living environments.

We looked for points in the complex system of relationships where a small action might make a big impact. The idea was to identify "assets"—aspects of the system that favored the elephants—and link these to reinforce each other. Assets ranged from individuals, organizations, and features of the environment to laws and traditions. At the same time we wanted to diminish aspects that were a threat.

This broader view provided more "pathways," more scope for discovering solutions and compromises.

The human environment was complex. Multiple ethnicities and livelihoods coexisted. Nomadic and semi-nomadic pastoralists shared space and water with settled farmers.

Clearing land for agriculture removed elephant habitat and obstructed access to water. This made crops vulnerable to trampling and hungry elephants. Ever-increasing numbers of cattle put pressure on water sources, soils and vegetation.

We found that local people valued Mali's elephants for multiple reasons—most strikingly because "if elephants disappear it means the environment is no longer good for us."

People also understood that human activity needed to respect environmental limits. Yet despite this, the environment was clearly degraded and over-exploited.

Further in-depth studies found that 96% of the cattle in the study area belonged to distant wealthy urbanites. They invested in cattle and sent them into more remote areas to find pasture and water. Many other natural resources (such as firewood, charcoal, game and wild foods) were also harvested by urban commercial interests.

And although each ethnic group sharing the area had its own systems to manage natural resources sustainably, they were reluctant to respect the enforcement systems of other groups. The result was shared resources such as pasture and forest being depleted by individual users for their immediate benefit.

Searching for solutions

In 2010 the project brought together the local communities to discuss these findings. Once unified around a shared understanding of the problems, they proposed a solution that also respected the needs of elephants. Their solution was modeled on traditional governance systems. A committee of elders set the rules of resource use and teams of young "ecoguards" would patrol to ensure the rules were respected. The ecoguards also conducted activities such as building firebreaks and planting trees.

The protection of an area of pasture with firebreaks meant, for example, that abundant pasture was available close by. People could sell fodder and grazing or water access rights. Their own animals were healthier and more productive and valuable. The protection of forest from exploitation by outsiders meant wood, forage, wild foods, medicines and other forest products could generate income from schemes managed by women's associations. This approach was possible because Mali's decentralization legislation puts natural resource management in the hands of local communities.

The conflict and lawlessness that have afflicted the area since 2012 presented huge challenges. The combination of a resurgence of Tuareg separatism, a military coup and a jihadist insurgency caused government to retreat from the north and center of Mali.

Despite these challenges, applying a complexity perspective to a problem of elephant conservation helped address several problems simultaneously.

Elephants avoided areas where they were poached and where armed groups were present. This pushed them into more populated areas where we could use the model to mitigate conflict.

Results

The approach helps elephants and humans to live together peaceably. It has also improved local livelihoods through more abundant natural resources. The collective nature of the solutions improved social cohesion because people had to work together to realize the benefits.

As one community ecoguard observed during a recent survey, "when you sit around the fire talking, having worked together all day, you realize that we all have the same problems." It has also countered youth unemployment by providing socially respected occupations in the restoration of ecosystems and biodiversity.

The resilience of the project in the face of insecurity seems to have been achieved because it was rooted in local and inclusive systems to solve local problems.

The approach has relevance for the Post-2020 Global Biodiversity Framework to be agreed at the next Conference of the Parties to the Convention on Biological Diversity in 2022, and its aim for a shared vision of living in harmony with nature by 2050.The way elephants raid crops in Kenya's Masai Mara has changedProvided by The Conversation 

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First reported case of anthrax in wildlife: Infected zebra most likely causes death of 3 cheetahs

by Forschungsverbund Berlin e.V. (FVB)

Collared cheetah in the Namib Desert. Credit: Ruben Portas

Anthrax is an infectious bacterial disease endemic in some parts of Africa. It affects people, livestock as well as wildlife. Using GPS telemetry data, a team of scientists from the Cheetah Research Project of the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW) reconstructed a special case of anthrax infection in Namibia: Three free-ranging cheetahs in the Namib Desert died within 24 hours after feeding on a mountain zebra that tested positive for the disease. The zebra is the first described case of a wild animal infected with anthrax in this arid region. The case also shows that there might be previously unknown risks to cheetah populations in the desert. It is described in detail in the scientific journal Frontiers in Veterinary Science.

Since 2015, scientists of the Leibniz-IZW Cheetah Research Project (CRP) conduct a National Cheetah Survey together with the Namibian Ministry of Environment, Forestry and Tourism (MEFT). The purpose is to obtain data on cheetah density and distribution across the country. Within this framework, a coalition of three cheetah males was captured in the Namib Desert and one animal equipped with a GPS collar. The recorded location and movement data were regularly downloaded during aerial tracking flights. On one of these flights, on October 5th 2019, the carcass of a collared cheetah—one of the members of the coalition—was located from the aircraft. During the following ground inspection, the other two cheetahs were also found dead. "The GPS data of the collared cheetah revealed that they died within a time window of six hours a few days before we found them," says Ruben Portas, CRP scientist. "Evaluating their most recent movements, we identified a cluster of GPS locations approximately two kilometers away from the location where they were found dead." At this spot the cheetahs spent 20 hours on the day before their death. When visiting this cluster, Portas found the carcass of an adult mountain zebra. The GPS and activity data from the collar suggested that the cheetahs fed on it. Bacillus anthracis, the cause of Anthrax infections, was isolated from buccal and nasal swabs collected from the dead zebra, making it the first confirmed anthrax infection in a wildlife species in the Namib Desert.

Carnivores are typically less susceptible to anthrax than herbivores. Cheetahs in particular have a high constitutive innate immunity which provides them with a rapid first line of defense against pathogens such as Bacillus anthracis. "However, when a high load of bacteria is ingested, for example with meat from a contaminated carcass, their potent constitutive innate immunity might be overloaded," explains CRP project head Bettina Wachter. "Cheetahs scavenge only rarely, which reduces their exposure to anthrax infected prey. As a result, they do not produce high antibody titres, which would be another line of defense. Thus, cheetahs die quickly when infected, as studies in Etosha National Park in northern Namibia have shown."

The pathogen was not detected in any of the three cheetahs found in the Namib, but the scientists consider it very likely that anthrax was the direct cause of their death. Bacterial cultures from highly susceptible animals that quickly die are often anthrax negative, because the animals might die already at a low presence of bacteria in the blood or from a high load of toxin released by Bacillus anthracis when destroyed by the immune system. Additionally, the vegetative form of the pathogen only develops when exposed to air quickly after the death of the host. The cheetahs were untouched for 11 days after their death and their bodies were not opened by scavengers, which might also explain the negative results of the lab tests for anthrax.

Anthrax is an unstudied disease in arid habitats. When wildlife dies in the Namib Desert, causes are often attributed to drought, hunger and the challenging desert conditions. "The few reported cases in which diseases such as anthrax were tested in the arid environments of Namibia are when livestock or people were directly affected," says Portas. "We do not know the prevalence of anthrax in the Namib desert and how wildlife populations are affected by the disease. For other habitats, such as the Etosha National Park, there is a large body of research showing that anthrax has a key ecological role in the environment."

This first confirmed case of anthrax in the Namib Desert in wildlife demonstrates that the disease might by endemic in the desert and other arid environments. Most of the Namib Desert is included in protected areas where cheetahs and other species find an important refuge from conflict with humans. Thus, this new knowledge may be important for assessing risks to the species. "Although few data are available, no other disease has shown such an impact on the cheetah population and certainly requires further research that may lead to appropriate conservation measures," Wachter concludes. "This study shows that data recorded by GPS collars have the potential to disclose additional important information in addition to spatial movement information."France begins vaccinating cows, sheep against anthrax

More information: Ruben Portas et al, GPS Telemetry Reveals a Zebra With Anthrax as Putative Cause of Death for Three Cheetahs in the Namib Desert, Frontiers in Veterinary Science (2021). DOI: 10.3389/fvets.2021.714758

Provided by Forschungsverbund Berlin e.V. (FVB)