Research on Syrian refugees suggests that exposure to extreme violence can cause epigenetic changes, specifically alterations to gene expression rather than the genes themselves, that can be passed down for at least two generations. The study found grandsons of men exposed to severe violence in the Syrian conflict showed altered stress hormone regulation, even though these grandsons never experienced the violence firsthand. This suggests trauma can have lasting biological consequences across generations through epigenetic inheritance.
Genetic analysis of killer whale scat collected around the Bremer Bay region of Australia confirms predation on white sharks. Researchers identified white shark DNA in multiple samples, including muscle and skin tissue. This provides direct dietary evidence supporting anecdotal observations of killer whale predation on white sharks in the area, including targeted attacks on the sharks' livers, a nutrient-rich organ. The study highlights the ecological role of killer whales as apex predators and their potential impact on white shark populations.
HN commenters discuss the methodology and implications of the study. Some question the small sample size (4 sharks with orca DNA) and suggest alternative explanations for the orca DNA presence, such as scavenging or secondary transfer. Others highlight the observed behavioral shift in white sharks avoiding areas where orcas are present, suggesting learned predator avoidance despite limited direct predation evidence. The discussion also touches on the ecological impact of apex predator interactions and the cascading effects on the ecosystem. Some express fascination with the topic and share anecdotal evidence or similar observations in other regions.
A new study combining ancient DNA analysis with linguistic and archaeological data suggests the Indo-European language family originated with the Yamnaya pastoralists who migrated from the Pontic-Caspian steppe into Europe around 5,000 years ago. These migrations, associated with the spread of wheeled vehicles and early horse domestication, brought the Yamnaya into contact with European hunter-gatherers, resulting in a genetic admixture that ultimately led to the Corded Ware culture. This Corded Ware population is identified as the source of later migrations eastward, spreading Indo-European languages across Europe and Asia.
Hacker News users discussed the methodology and implications of the study. Several commenters questioned the reliability of inferring large-scale migrations and cultural shifts solely from genetic data, emphasizing the complexity of language evolution and its potential disconnect from genetic lineages. Some pointed to known instances of language replacement without significant population change, highlighting the limitations of using genetics as the sole indicator. Others debated the specific migration routes proposed in the study and alternative theories regarding the spread of Indo-European languages. The discussion also touched on the sensitivity surrounding research into ancient populations and the importance of respectful and accurate interpretation of findings. Some users expressed concern about potential misuse of such research to support nationalist narratives.
The essay "In Praise of Subspecies" argues for the renewed recognition and utilization of the subspecies classification in conservation efforts. The author contends that while the concept of subspecies has fallen out of favor due to perceived subjectivity and association with outdated racial theories, it remains a valuable tool for identifying and protecting distinct evolutionary lineages within species. Ignoring subspecies risks overlooking significant biodiversity and hindering effective conservation strategies. By acknowledging and protecting subspecies, we can better safeguard evolutionary potential and preserve the full richness of life on Earth.
HN commenters largely discussed the complexities and ambiguities surrounding the subspecies classification, questioning its scientific rigor and practical applications. Some highlighted the arbitrary nature of defining subspecies based on often slight morphological differences, influenced by historical biases. Others pointed out the difficulty in applying the concept to microorganisms or species with clinal variation. The conservation implications were also debated, with some arguing subspecies classifications can hinder conservation efforts by creating artificial barriers and others suggesting they can be crucial for preserving unique evolutionary lineages. Several comments referenced the "species problem" and the inherent challenge in categorizing biological diversity. A few users mentioned specific examples, like the red wolf and the difficulties faced in its conservation due to subspecies debates.
During the 900-day siege of Leningrad in World War II, the Vavilov Institute, home to a vast collection of seeds and plant material, became a poignant symbol of resistance and sacrifice. Facing starvation, the scientists working there protected the invaluable collection, even choosing to die of hunger rather than consume the edible seeds and tubers under their care. This act of extraordinary dedication preserved crucial biodiversity for future generations, highlighting the enduring power of scientific commitment amidst unimaginable hardship. The article explores this story, emphasizing the difficult ethical decisions faced by the scientists and the lasting legacy of Nikolai Vavilov, the Institute's founder who perished in a Stalinist prison.
HN commenters largely focused on the astounding dedication of Vavilov and his team of scientists. Several highlighted the irony of researchers starving to death amidst a seed bank containing the potential to alleviate global hunger. Some debated the practicality of seed saving in a besieged city, questioning if distributing the food would have been a better short-term solution. Others drew parallels to contemporary seed banks like the Svalbard Global Seed Vault, emphasizing the importance of preserving biodiversity. A few comments offered additional historical context about Lysenko and his detrimental impact on Soviet agriculture, or about other sieges where similar acts of sacrifice occurred. Several commenters expressed gratitude for the article, finding it both informative and moving.
The "Third Base" article explores the complex role of guanine quadruplexes (G4s), four-stranded DNA structures, in biology. Initially dismissed as lab artifacts, G4s are now recognized as potentially crucial elements in cellular processes. They are found in telomeres and promoter regions of genes, suggesting roles in aging and gene expression. The article highlights the dynamic nature of G4 formation and how it can be influenced by proteins and small molecules. While research is ongoing, G4s are implicated in both vital functions and diseases like cancer, raising the possibility of targeting them for therapeutic interventions.
Hacker News users discuss the surprisingly complex history and evolution of third base in baseball. Several commenters highlight the article's insightful explanation of how the base's positioning has changed over time, influenced by factors like foul territory rules and the gradual shift from a "bound catch" rule to the modern fly catch. Some express fascination with the now-obsolete "three strikes and you're out if it's caught on the first bounce" rule. Others appreciate the detailed descriptions of early baseball and how the different rules shaped the way the game was played. A few commenters draw parallels between the evolution of baseball and the development of other sports and games, emphasizing how seemingly arbitrary rules can have significant impacts on strategy and gameplay. There is general appreciation for the depth of research and clear writing style of the article.
Summary of Comments ( 205 )
https://news.ycombinator.com/item?id=43206722
HN commenters were skeptical of the study's methodology and conclusions. Several questioned the small sample size and the lack of control for other factors that might influence gene expression. They also expressed concerns about the broad interpretation of "violence" and the potential for oversimplification of complex social and biological interactions. Some commenters pointed to the difficulty of isolating the effects of trauma from other environmental and genetic influences, while others questioned the study's potential for misinterpretation and misuse in justifying discriminatory policies. A few suggested further research with larger and more diverse populations would be needed to validate the findings. Several commenters also discussed the ethics and implications of studying epigenetics in conflict zones.
The Hacker News post titled "Violence alters human genes for generations, researchers discover," linking to a University of Florida news article about a study on the epigenetic effects of violence in Syria, has generated several comments. Many commenters express skepticism and raise methodological concerns about the study.
One recurring theme is the difficulty of isolating the effects of violence from other factors like poverty, malnutrition, and displacement, which often accompany conflict. Commenters argue that these confounding variables could also have significant epigenetic impacts, making it hard to attribute the observed changes solely to violence. Some suggest that the study should have included a control group experiencing similar hardships but not direct violence to better isolate the variable of interest.
Another point of contention is the small sample size of the study. Several commenters point out that with a limited number of participants, the results might not be generalizable to the broader Syrian population or other populations affected by conflict. They call for larger-scale studies to validate the findings.
Several commenters also critique the framing of the research and the news article. They argue that using terms like "altered genes" can be misleading to the public, as epigenetics involves changes in gene expression rather than alterations to the underlying DNA sequence. They worry that such phrasing could perpetuate misconceptions about the nature of inheritance and the immutability of genes.
Some commenters question the causal link implied by the study. They point out that while the study shows a correlation between exposure to violence and epigenetic changes, it doesn't definitively prove that violence causes these changes. They suggest that the relationship could be more complex and involve other mediating factors.
A few commenters raise concerns about the potential ethical implications of the research. They worry that linking violence to heritable epigenetic changes could lead to stigmatization or discrimination against certain groups.
In addition to these critiques, some commenters express interest in further research on the topic. They suggest exploring the potential reversibility of these epigenetic changes and the long-term health consequences for future generations. Some also call for more research into the epigenetic effects of other types of trauma and adversity. Despite the expressed interest, the dominant tone of the comments is one of cautious skepticism about the study's conclusions and methodology.