Science

Summary from the 404 media newsletter

Heart cockles, a group of marine molluscs, contain little communities of algae in their shells as part of a symbiotic relationship; the algae get shelter and protection, and the cockles get algae-processed nutrients.

Now, scientists have discovered that cockle shells have a host of mind-boggling adaptations to keep these algae happy, including windows that offer “the first example of fiber optic cable bundles in a living creature.”

“We show that the fibrous prismatic crystals act like parallel bundles of fiber optic cables in the shell windows, not just transmitting light but projecting high-resolution images through the window,” that have “a resolution of >100 lines/mm,” said researchers led by Dakota McCoy of the University of Chicago.

From the article in the link above:

Fig. 1: Heart cockles (Corculum cardissa and Corculum spp.) are asymmetrical, photosymbiotic bivalves.

Fig. 2: Transparent windows allow heart cockle shells to transmit 11–62% of photosynthetically active radiation (mean = 31%) and significantly screen out UV radiation (mean = 14%, range = 5–28%).

Scientists have broken the record for the world’s thinnest pasta with a new “nanopasta” that measures just 372 nanometers, which is 200 times thinner than a strand of human hair. Britton, Beatrice et al.

“By dissolving 17 wheat flour in warm formic acid and cooling, a dope can be created which can be electrospun into porous mats of 372 nm fibers of pasta,” said researchers led by Beatrice Britton of University College London. “The pasta was made by applying an electric charge to a starch solution which is ejected towards a grounded substrate while drying during flight.”

Abstract

: This study examines the effects of misleading news—one type of false information presented by news media in the U.S. and China—in the context of international disputes.

Through a web-based survey experiment, we tested how Chinese readers’ perception of false news is affected by the source of the news, the presence of visual elements, and general trust in mainstream Chinese media and that in mainstream U.S. media, as well as news literacy.

Our results suggested false news reported by domestic media was perceived to better represent the reality of the covered issue than news presented by foreign media. This relationship was moderated by readers’ general trust in U.S. media and news literacy, which indicated media literacy training as a possible solution to counteract the effect of the news source.

These findings not only advance current scholarship on misinformation by incorporating perspectives from non-Western media systems but also provide both foreign and domestic readers with timely and relevant methods to combat false information.

Abstract

: The increasing prevalence of disinformation has become a global challenge, exacerbated by the rapid dissemination of information in online environments. The present study conducts a bibliometric analysis of scholarly efforts made over time in the research papers associated with the disinformation field. Thus, this paper aims to understand and help combat disinformation by focusing on methodologies, datasets, and key metadata. Through a bibliometric approach, the study identifies leading authors, affiliations, and journals and examines collaboration networks in the field of disinformation. This analysis highlights the significant growth in research on disinformation, particularly in response to events such as the 2016 U.S. election, Brexit, and the COVID-19 pandemic, with an overall growth rate of 15.14% in the entire analyzed period.

The results of the analysis underscore the role of social media and artificial intelligence in the spread of disinformation, as well as the importance of fact-checking technologies. Findings reveal that the most prolific contributions come from universities in the United States of America (USA), the United Kingdom (UK), Spain, and other global institutions, with a notable increase in publications since 2018.

Through thematic maps, a keyword analysis, and collaboration networks, this study provides a comprehensive overview of the evolving field of disinformation research, offering valuable insights for future investigations and policy development.

Abstract

The aim of the current study is to evaluate the radioactivity estimate the radiological risk of some granites and marbles rocks and explaining the cause of increased radioactivity in some types of rocks. The radioactivity of some granites and marbles produced in Egypt were determined by using a Germanium detector. Three types of marble (Breshia, Galala, and Trista) and three types of granite (Gandola, White Halayeb, and Red Aswani) were collected. All marble samples show low radioactivity with average activity concentrations of 20 ± 2, 4.50 ± 0.5, and 6.70 ± 1.2 Bqkg^− 1^ for ^226^Ra, ^232^Th, and ^40^K respectively. Granite samples have higher activity concentration with averages of 152 ± 7, 129 ± 8, and 1228 ± 15 Bqkg^− 1^ for ^226^Ra, ^232^Th, and ^40^K respectively which exceed the world average values of soil (32,45,412 Bqkg− 1 for 226Ra, 232Th, and 40K respectively) excluding Granite G.2 (white Halayeb) as it shows an insignificant level of radioactivity. The annual effective doses of marble samples Breshia, Galala, and Trista were measured to be 4.42 ± 0.4; 158 ± 14 and 153 ± 15 µSvy^− 1^, and 1008 ± 147, 80 ± 7 and 987 ± 45.0 µSvy^− 1^ for the granite samples Gandola, White Halayeb and Red Aswani respectively. The radiation hazard parameters show a higher value for granite samples than marble samples, primarily due to the presence of potassium feldspar minerals in these types of granites. marbles were observed to be radiologically safer than granite because they possess a neglected ^40^K content and a trace quantity of uranium and thorium. Moreover, the minimum potassium content is enough to make a rock radiological unsafe due to ^40^K only being determined to be about 13.2%.

The paper, in a very funny but serious way, makes a strong case for the relative uselessness of the index finger, and it's recommendation for amputation if it's at all damaged and impeding existence.

Discoveries about a young ancestor's teeth may shed light on the upward trend in brain size over millennia.

Other explanations

Bipedalism developed long before bigger brains, and the use of tools was widespread in earlier hominid branches. As a result, these causes have been ruled out as the main driving force in brain evolution, despite being essential preconditions. https://efossils.org/book/bipedalism-vs-brain-size

Preteen teeth

The recent study of the 1.77 Million-year-old remains of an 11 to 12-year-old early homo from the Dmanisi site in Georgia is significant. https://phys.org/news/2024-11-fossil-teeth-childhood-prelude-evolution.html. This study of dental development throws some light on another human oddity, which is our very extended childhoods. The fossil's age places it close to the emergence of larger brains in our ancestors. A useful timeline is found here https://australian.museum/learn/science/human-evolution/larger-brains/

For context that's around this point in Human Evolution

Modern Human life history is distinguished by a prolonged childhood in which mental and somatic development rates diverge. This slow development is crucial for developing high cognitive abilities in our socially complex species.

A slowing childhood in a supportive family and cultural transmission

This individual experienced rapid growth in their first five years, faster than in apes. For example, their wisdom teeth fully emerged at 12 years of age compared to 17-24 today. This rapid growth was unexpected given the age of the fossil and its relationship to modern humans. However, the teeth did have a sequence of growth similar to modern humans. Marcia Ponce de León from the University of Zurich and co-author of the study commented "Milk teeth were used for longer than in the great apes and the children of this early Homo species were dependent on adult support for longer than those of the great apes". She suggests that "This could be the first evolutionary experiment of prolonged childhood".

It is believed that children's development slowed as cultural transmission increased, making the quantity of knowledge conveyed from old to young more crucial. This transmission would have allowed them to make greater use of available resources while developing more sophisticated behaviours, providing them with an evolutionary advantage.

The demands of large brains cause Humans to develop more slowly than our closest animal cousins. Energy directed toward the brain dominates the human body's metabolism early in life, which is possibly one other reason why humans develop at a rate more akin to a reptile than a mammal in early childhood. A five-year-old's brain is a real energy monster. It uses twice as much glucose as a fully grown adult. See https://www.sciencedaily.com/releases/2014/08/140825152558.htm

What does this explain?

However, just identifying some of the forces influencing the brain's evolution does not account for the emergence of more recent advances such as symbolic language. https://www.britannica.com/science/human-evolution/Language-culture-and-lifeways-in-the-Pleistocene Nonetheless, the brain's expansion was an essential precursor to the richness of human culture. Even in this early era of human evolution where children needed to mature rapidly, and life expectancy was low, adult care exerted a protective effect.

Additional Info

A variety of circumstances probably influenced brain development, including contributions from diverse hominid lineages with larger brains that were previously lumped into a single smaller smaller-brained species. Ian Tattersall provides a nuanced discussion of brain size and how it relates to humanities tangled origins in this 2023 article: Endocranial volumes and human evolution, https://pmc.ncbi.nlm.nih.gov/articles/PMC10517302/

I was searching online for quite a while this evening, chasing a half-remembered bit of trivia, that trilobites were supposedly unique in their use of calcite for their lenses, composing the ommatidia of their compound eyes.

It must be so obvious to scientists in the field of studying insects that they never mention it in their papers...

So, what compound(s) do modern arthropods use in their compound eyes. If it isn't calcite, what do modern 'bugs' use?

According to Khamis, this is the first time that the African native smaller mealworms' ability to decompose plastics has been recorded.

She stated that while Africa generates only 5 percent and uses 4 percent of global plastic, there is an increase in the usage of single-use plastic, making the continent the second most polluted.

Khamis said scientists tested the ability of the lesser mealworm to consume polystyrene, one of the major microplastics that is fast accumulating both in land and water bodies.

Males of the four Ptiloris species, a group within the birds of paradise native to Australia and New Guinea, have long fascinated biologists as well as female birds with their courtship displays. A male repeatedly fans out dark satiny wing feathers into a curved arc. He sways his head rhythmically and opens his mouth to a soundtrack of short, sharp thwacking sounds.

A 1930s-era breakthrough is helping physicists understand how quantum threads could weave together into a holographic space-time fabric.