Is Social Media Influencing Our Opinions Or Exposing Them? We Discuss With Dominique Brossard

admin

Is Social Media Influencing Our Opinions Or Exposing Them? We Discuss With Dominique Brossard

Jun 20, 2019 | Uncategorized

In this weeks episode, we discuss the good, the bad and the ugly impact social media and other modern communication methods are having on the way we form opinions. We’re joined by Dominique Brossard, an expert on media, science and policy, science and social media, public understanding of science, public attitudes toward controversial science. She sheds light on the impact of modern communication channels.

Resources mentioned:

Dominique’s university profile and contact information:https://experts.news.wisc.edu/experts/dominique-brossard

More SciPods Radio episodes you may like

Harsanti Morley – Robert Morley | Reading Ancient Pollen to Reconstruct a Lost World in Java

Audiobook

scipod.global

About this episode

More than a million years ago, the island of Java looked very different from the busy, densely populated place we know today. Vast mangrove forests spread along muddy coastlines. Freshwater swamps stretched inland. Grasslands burned during dry seasons, while volcanic mountains rose in the distance beneath shifting tropical skies. Hidden within these ancient landscapes were animals that no longer exist and environments that shaped some of the earliest chapters of human history in Southeast Asia. A recent study by Harsanti Morley of Palynova Ltd and Robert Morley, who is a research associate at Royal Botanic Gardens, Kew, has opened an extraordinary window into that vanished world. By examining microscopic grains of fossil pollen and spores preserved in ancient rocks from Central Java, the researchers reconstructed ecosystems that existed during the early Pleistocene, a period beginning more than two million years ago. Their work reveals what the landscape looked like, and also how climate, sea levels, vegetation, and wildlife changed through time. More

The study focused on the Kalibiuk and Kaliglagah Formations near the village of Bentasari in Central Java. These rock formations are especially important because they contain fossils older than the earliest known remains of Homo erectus in Java. Long before modern cities and rice fields appeared, this region was part of a dynamic coastal environment shaped by rivers, tides, monsoon climates, and volcanic activity.

To uncover the story hidden inside the rocks, the researchers collected dozens of sediment samples from a one hundred meter section of exposed strata. Inside each sample were fossil pollen grains, spores from ferns, freshwater algae, and tiny fragments of ancient plant tissue. These microscopic remains act like environmental fingerprints. Different plants produce distinct forms of pollen and spores, allowing scientists to identify what kinds of vegetation once dominated the region.

Palynology, the study of fossil pollen and spores, may sound highly specialized, but it offers one of the most powerful tools for reconstructing ancient environments. Pollen grains are remarkably durable. Once buried in mud or sediment, they can survive for millions of years. By identifying the types and abundance of pollen in different layers of rock, researchers can track environmental changes through time with remarkable precision.

What Harsanti Morley and Robert Morley discovered was a landscape that shifted repeatedly between marine and freshwater conditions. In the older parts of the sequence, the coastline was dominated by extensive mangrove forests. The pollen record showed overwhelming evidence of mangrove trees from the Rhizophoraceae family, accompanied by Sonneratia trees, mangrove palms, and salt-tolerant ferns.

These mangroves formed part of a huge tropical delta system where rivers met the sea. Some areas were muddy tidal flats, while others supported dense mangrove stands growing directly at the site where sediments accumulated. The evidence even suggests that sea levels rose and fell in repeating cycles, causing the coastline to advance and retreat over time.

The researchers believe the sediments captured two major environmental cycles linked to variations in Earth’s orbit. During the early Pleistocene, global climate patterns were strongly influenced by changes in the tilt of Earth’s axis, known as obliquity cycles. Each cycle lasted roughly forty one thousand years. As climate and sea levels shifted, the delta expanded and contracted, creating new habitats across the landscape.

One of the most striking discoveries involved the role of the mangrove fern Acrostichum. In some layers, spores from this fern became extraordinarily abundant, suggesting that it temporarily dominated large stretches of the delta plain. Today, Acrostichum often flourishes in disturbed coastal environments, and its abundance in the fossil record may point to periods of ecological disruption.

As conditions became more freshwater influenced, the environment changed dramatically. The younger parts of the sequence recorded freshwater swamps filled with plants such as Jussiaea, Pandanus, Polygonum, and Hanguana. Open pools of water supported algae, while grasses and sedges spread across the wetlands.

Yet the most surprising feature of the ancient landscape may have been what existed beyond the swamps. The pollen record showed enormous quantities of grass pollen, along with charred fragments of grass cuticle. These fragments provide evidence of repeated burning. According to the researchers, the surrounding lowlands were probably covered by open grassy savanna rather than dense tropical rainforest.

This conclusion challenges older ideas that early Pleistocene Java was dominated by lush lowland rainforest. Instead, the evidence points toward a strongly seasonal climate with long dry periods that allowed fires to spread across grasslands. Trees certainly existed, especially along rivers and in scattered forest patches, but open vegetation appears to have been widespread.

At the same time, the mountains in the distance supported cooler montane forests. Pollen from podocarps, oaks, and other upland trees drifted into the delta system from higher elevations. The result was a landscape of extraordinary ecological diversity. Coastal mangroves bordered freshwater swamps, open savannas stretched across the lowlands, and forested volcanic mountains towered above everything.

The study also provides clues about the animals that once inhabited the region. Earlier fossil discoveries from the Kaliglagah Formation included unusual species such as pygmy hippopotamuses and giant tortoises. The swampy, grassy environment reconstructed from the pollen evidence may have provided ideal habitat for these animals.

The researchers even suggest that some of the freshwater swamps may have been repeatedly disturbed by large herbivores. Certain plants found in the pollen record, including Jussiaea and Polygonum, often thrive in disturbed wetland environments today. Ancient animals moving through the swamps could have helped maintain these open wetland habitats.

Perhaps most importantly, the findings help scientists better understand the environmental setting that existed just before and during the arrival of early humans in Java. Homo erectus eventually became one of the most successful early human species, spreading far beyond Africa into Asia. Understanding the environments these early humans encountered is essential for reconstructing how they adapted and survived.

The Bentasari study suggests that early humans entering Java may have encountered a mosaic of open grasslands, wetlands, mangroves, and volcanic uplands rather than endless rainforest. Open environments could have provided opportunities for hunting, scavenging, and movement across the landscape.

Another important discovery involved a fossil spore called Stenochlaenidites papuanus. This ancient plant type disappeared from the Sunda region around one and a half million years ago. Its presence in the Bentasari sediments confirms that the deposits belong to a very early chapter of the Pleistocene. The same spore has been found at a few other important fossil localities in Java, helping scientists compare the ages of different sites across the island.

The work also highlights how much information can be preserved in microscopic fossils that most people would never notice. A grain of pollen smaller than the width of a human hair can reveal whether ancient coastlines supported mangroves, whether grasslands burned during droughts, or whether mountain forests flourished nearby.

Studies like this remind us that Earth’s environments are constantly changing. Coastlines shift, climates fluctuate, ecosystems expand and disappear, and species adapt or vanish. The tropical landscapes of ancient Java were shaped by forces that still operate today, including sea level change, climate cycles, volcanic activity, and fire.

At the same time, the research carries a modern message. Many of the ecosystems reconstructed in the study, especially mangroves and freshwater swamps, are now heavily damaged or disappearing across Southeast Asia. Understanding how these environments evolved over immense stretches of time can help scientists appreciate their resilience, but also their vulnerability.

Download .mp3

Original article reference

This Audio is based on the paper “Palynology of the Early Pleistocene Kalibiuk and Kaliglagah Formations at Bentasari, Central Java, Indonesia,” in Review of Palaeobotany and Palynology, https://doi.org/10.1016/j.revpalbo.2025.105352

Funding

Funding for this research was provided by Palynova Ltd.

Contact

For further information, please contact Harsanti Morley at santimorley@mac.com or Robert Morley at bobmorley100@gmail.com

This work is licensed under a Creative Commons Attribution 4.0 International License.

What does this mean?

Share: You can copy and redistribute the material in any medium or format

Adapt: You can change, and build upon the material for any purpose, even commercially.

Credit: You must give appropriate credit, provide a link to the license, and indicate if changes were made.

Increase The Impact Of Your Research!

Create your Audiobook

More episodes

Karl Fleming | Balancing Safety: Rethinking Prevention and Mitigation in a Complex World

Audiobook

scipod.global

About this episode

In the world of nuclear energy, safety is not a single switch that can be turned on or off. It is a layered, evolving philosophy shaped by decades of engineering, research, and experience. At the heart of this philosophy lie two deceptively simple ideas: prevention and mitigation. These terms sound straightforward, yet their meaning becomes far more intricate when applied to modern reactor systems. The paper authored by Karl Fleming of KNF Consulting Services, and colleagues, invites us to rethink what these concepts truly mean, especially as nuclear technology advances into new territory. More

Traditionally, prevention has been understood as stopping something bad from happening, while mitigation focuses on limiting the damage if it does. In older nuclear reactor designs, these ideas often revolved around preventing core damage and mitigating the consequences if such damage occurred. But as reactor designs diversify and become more sophisticated, these definitions begin to fall short. Advanced reactors do not always fit neatly into the old frameworks, and the concept of “core damage” itself may not even apply in the same way.

An industry team of reactor safety experts recognized this gap and set out to redefine prevention and mitigation in a way that could work across a wide range of reactor designs. This team was responsible for developing the Licensing Modernization Project (LMP) led by Southern Company under contract with the U.S. Department of Energy to support the design and licensing of advanced reactor technologies. This project has advanced and is grounded in a broader, more flexible way of thinking about risk. Instead of focusing on a single failure point, they consider entire sequences of events that could unfold during an incident. This shift in perspective changes everything.

Imagine a chain reaction of events triggered by a disturbance in a nuclear plant. Each step along that chain presents an opportunity to either prevent the situation from escalating or to mitigate its consequences. In this framework, prevention and mitigation are no longer fixed labels assigned to specific systems. Instead, they become dynamic roles that systems play depending on where they are in the sequence.

For example, a system that successfully stops an initial disturbance from becoming a more serious event can be seen as performing a preventive function. But if that same system acts later to limit damage after a failure has already occurred, it is performing a mitigating function. The distinction is not about the system itself but about its role in the unfolding scenario.

This insight is one of the most powerful contributions of LMP’s team work. It reveals that prevention and mitigation are not mutually exclusive categories. In fact, most safety systems do both. Their reliability helps prevent more severe outcomes, while their capability helps reduce the consequences when challenges arise. This dual role highlights the importance of designing systems that are both dependable and effective under stress.

To better understand this idea, consider how reactor safety experts model potential accidents. They use what is known as a probabilistic risk assessment, which maps out different sequences of events and assigns probabilities to each step. These models allow safety experts to explore countless scenarios, from minor disturbances to rare but severe accidents. Within each scenario, systems succeed or fail in different ways, shaping the final outcome.

In this context, prevention is reflected in the likelihood that a system will succeed in stopping an event from progressing. Mitigation, on the other hand, is reflected in how well the system can limit the consequences if it is called upon to act. By analyzing both aspects together, engineers can gain a much deeper understanding of how safety is achieved by achieving reliability in prevention and capability in mitigation.

One of the key ideas emphasized in the LMP is that safety cannot be reduced to a simple balance between prevention and mitigation. It is tempting to imagine a scale where more prevention means less need for mitigation, or vice versa. But real systems are far more complex. Each possible event sequence has its own unique combination of preventive and mitigating actions, and the overall safety of a plant depends on the full spectrum of these sequences.

Interestingly, patterns do emerge when looking across many scenarios. More frequent events tend to rely heavily on mitigation. These are situations that are expected to occur occasionally, so systems are designed to handle them effectively and limit their impact. Rare events, by contrast, rely more on prevention. Because their consequences can be severe, the focus is on reducing their likelihood as much as possible.

This pattern reflects a broader principle known as defense in depth. Rather than relying on a single line of defense, nuclear safety is built on multiple layers of protection. Some layers aim to prevent problems from occurring, while others are designed to manage the consequences if they do. Together, these layers create a resilient system that can withstand a wide range of challenges.

The work described in Fleming’s paper also highlights the importance of performance-based design. Instead of prescribing exactly how systems must be built based on satisfying rules, this approach focuses on what they must achieve in terms of performance attributes than can be observed, measured, or calculated. Engineers set targets for reliability and capability, ensuring that systems perform their safety functions effectively. These targets are informed by risk assessments, creating a direct link between design decisions and safety outcomes.

This shift toward performance-based thinking is particularly important for advanced reactors. These designs often incorporate new materials, new fuels, and new ways of containing radioactive materials. A one-size-fits-all approach simply does not work. By focusing on performance and risk, engineers can tailor safety strategies to the unique characteristics of each design while providing a uniform level of safety.

Another important aspect of this approach is the recognition that safety is not static. As designs evolve and new information becomes available, risk assessments can be updated, and safety measures can be refined and adapted to changes. This iterative process ensures that safety remains robust even as technology advances.

The practical implications of this work are significant. By redefining prevention and mitigation in a more flexible and comprehensive way, nuclear safety experts are able to provide a framework that can be applied to both existing and future reactors. This framework helps engineers identify which systems are most important for safety, how they should be designed, and how their performance should be monitored.

It also offers a clearer way to evaluate whether a plant has adequate defense in depth. Instead of relying on abstract principles, engineers can examine how different systems contribute to preventing and mitigating specific event sequences. This detailed understanding makes it easier to identify potential weaknesses and address them before they become problems.

Perhaps most importantly, this work underscores the idea that safety is not about eliminating risk entirely. In complex systems, some level of risk is inevitable. The goal is to understand that risk, manage it effectively, and ensure that no single failure can lead to unacceptable consequences.

By embracing this perspective, the nuclear industry can continue to innovate while maintaining high standards of safety. The insights provided by Karl Fleming and the LMP team represent a significant step forward in this effort. They remind us that safety is not just about building stronger systems, but about thinking more deeply about how those systems interact and perform under real-world conditions.

The story of prevention and mitigation is not just about nuclear reactors. It is a story about how we approach complex challenges in an uncertain world. It is about recognizing that problems rarely have simple solutions, and that true resilience comes from understanding the interplay of many factors. Through this lens, the work of Karl Fleming and the LMP team offers lessons that extend far beyond the boundaries of engineering, inviting us to rethink how we design for safety in all aspects of modern life.

Download .mp3