The Skeptics' Guide to the Universe

The Skeptics Guide #1067 - Dec 20 2025

December 20, 2025

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  • Animals are undergoing evolutionary adaptation, driven by proximity to humans and selective pressures (like culling aggressive individuals), leading to reduced aggressiveness, as evidenced in brown bears and coyotes. 
  • The ethical debate surrounding xenotransplantation is currently focused on the NIH moratorium against growing human organs in animal hosts (like pigs) due to concerns over creating human-animal chimeras, despite the ongoing success of transplanting modified pig organs. 
  • The historical European folk practice of children sucking on ant-covered straws to absorb vitality is scientifically linked to sympathetic magic, but the resulting sour taste is likely due to formic acid secreted by ants. 
  • Folklore involving consuming ants for vitality is rooted in sympathetic magic, though the sour taste is scientifically explained by formic acid, which offers no proven health benefits. 
  • Ants can act as a natural delivery system for lactic acid bacteria, potentially creating a yogurt-like food through fermentation, which aligns with the modest, strain-specific benefits of modern fermented foods. 
  • New evidence suggests Neanderthals were actively *making* fire 400,000 years ago by using flint and pyrite, significantly pushing back the timeline for controlled fire creation beyond previous estimates. 

Segments

Vaccination Experiences and Shingles
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(00:00:03)
  • Key Takeaway: Simultaneous administration of flu and COVID-19 vaccines can result in a stronger localized reaction and systemic sickness compared to receiving them separately.
  • Summary: The host experienced a significant localized arm reaction after receiving a COVID booster in the same arm immediately following a flu shot. Shingles vaccination is strongly recommended after age 50 due to the potential for severe, long-lasting post-herpetic neuralgia.
Animal Adaptation to Humans
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(00:07:44)
  • Key Takeaway: Isolated populations of brown bears in Italy show genetic markers for reduced aggressiveness, mirroring changes seen in domesticated animals due to proximity to human habitation.
  • Summary: The Russian fox experiment demonstrated that selecting for reduced aggression rapidly leads to physical traits associated with domestication, like floppy ears. In wild animals, reduced aggression is a selective advantage when food sources are available near human settlements, as seen in wolves evolving into dogs through self-domestication. Human activity, including killing aggressive animals, acts as a secondary selective pressure favoring more docile traits.
Crows Cleaning Up Litter
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(00:20:04)
  • Key Takeaway: A Swedish startup successfully trained crows using food rewards via ATM-like devices to collect and deposit cigarette butt litter.
  • Summary: Crows learned to deposit cigarette butts into specialized machines in exchange for food pellets, demonstrating high cognitive ability to solve complex environmental problems. However, this practice is noted as potentially increasing cancer rates among the crows due to exposure to the collected waste.
Ethics of Pig Organ Transplants
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(00:20:50)
  • Key Takeaway: The NIH moratorium on funding research to grow human organs inside pigs is based on ethical concerns about creating human-animal chimeras, specifically regarding potential cognitive alteration, despite the urgent need for kidneys.
  • Summary: While genetically modified pig kidneys are being transplanted into humans with temporary success, the goal of growing recipient-specific human organs inside pigs is stalled by a 2015 funding pause. The ethical concern centers on the fear that human cells migrating to neural tissue could create a sentient, human-like creature, which is scientifically incoherent but reflects a fear of human exceptionalism being violated.
Japan’s Space Solar Power Plan
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(00:38:05)
  • Key Takeaway: Japan is testing space-based solar power (SBSP) beaming energy via microwaves to address its severe energy import dependency, despite current high costs compared to ground solar.
  • Summary: SBSP offers 24/7 energy collection with 40 times the output potential of ground systems because it avoids nighttime and weather interference. Power is transmitted using microwaves captured by rectifying antennas (rectennas) on Earth, which convert the waves into DC electricity. While current cost estimates are significantly higher than ground solar, Japan’s lack of land for ground arrays makes SBSP a viable alternative if costs can approach those of nuclear power.
Ants and Folk Medicine
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(00:55:28)
  • Key Takeaway: A European folk practice involved children sucking on straws that ants had crawled on to absorb the insects’ vitality, which is an example of sympathetic magic.
  • Summary: This practice is categorized as sympathetic magic, where consuming something associated with an energetic creature (like ants) is believed to transfer its qualities. The sour or bitter taste experienced when sucking the straw is scientifically explained by the formic acid secreted by the ants.
Ant Folklore and Sympathetic Magic
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(00:57:31)
  • Key Takeaway: Folklore suggesting health benefits from consuming ants is categorized as sympathetic magic, where qualities are absorbed via contact or consumption.
  • Summary: Children historically sucked on straws from ant hills to gain vitality, believing they absorbed the ants’ resilience. This practice falls under sympathetic magic, where qualities are absorbed through contact or ingestion. The sour taste experienced is due to formic acid produced by ants, but ingesting these tiny amounts offers no proven health benefits.
Ants in Fermented Yogurt
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(00:59:21)
  • Key Takeaway: Ants in Eastern Europe served as a delivery system for lactic acid bacteria, naturally fermenting milk into a yogurt-like food.
  • Summary: In some regions, ants were added to warm milk to ferment it, producing a yogurt-like food. The ants carried lactic acid bacteria that lowered the milk’s pH, causing it to curdle. While the resulting product might offer modest benefits associated with fermented foods, isolating the bacteria directly yields the same results without needing the ants.
Health Benefits of Fermented Foods
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(01:00:34)
  • Key Takeaway: Evidence for routine health benefits from probiotics in fermented foods is thin, supporting only narrow applications like preventing antibiotic-associated diarrhea.
  • Summary: Fermented foods like yogurt may offer modest health benefits, specifically strain-specific advantages for lactose digestion or preventing diarrhea associated with antibiotic use, according to the AGA and WGO. The evidence only strongly supports high-colony-count probiotics taken immediately before initiating antibiotics. Routine use for general gut health is not supported by current evidence.
Reindeer Blood Bathing Folklore
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(01:02:34)
  • Key Takeaway: The practice of bathing in reindeer antler blood, allegedly used by Vladimir Putin, is another example of folklore based on absorbing qualities through contact.
  • Summary: Bathing in reindeer antler blood is cited as an example of sympathetic magic, similar to the ant consumption folklore. This practice is rooted in Siberian folklore, suggesting an attempt to absorb power or vitality from the animal. There is no scientific basis or evidence supporting any health or vitality benefits from this practice.
Evidence for Hominid Fire Making
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(01:03:24)
  • Key Takeaway: New evidence from Eastern England suggests Neanderthals were making fire 400,000 years ago, distinct from previously established evidence of opportunistic fire use.
  • Summary: Evidence for fire use by hominids dates back 1.5 million years, likely opportunistic use like lightning strikes, evidenced by charred bones. The new finding provides convincing evidence for fire making by Neanderthals 400,000 years ago at a site containing both flint and non-local iron pyrite. The presence of both materials, subjected to high temperatures alongside burned bones, strongly implies intentional ignition.
Mercury in Fish and Bioengineering Solutions
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(01:12:08)
  • Key Takeaway: Bioengineering minnows with plant genes that convert toxic methylmercury into gaseous mercury is being investigated to reduce mercury bioaccumulation in fish.
  • Summary: Mercury, primarily from coal-fired plants, enters the ecosystem, is converted to toxic methylmercury by bacteria, and bioaccumulates up the food chain, leading to high levels in game fish. Researchers are inserting plant genes into minnows, which are prey for game fish, to allow the minnows to convert methylmercury into a gaseous form released into the atmosphere. This genetic engineering aims to cut off the mercury accumulation chain in aquatic systems.
Compounding Pharmacy Regulation Clarification
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(01:17:02)
  • Key Takeaway: Compounding pharmacies are legitimate, regulated entities that customize FDA-approved drug components into specific formulas, contrary to the belief they are unregulated alternative medicine.
  • Summary: Compounding pharmacies are run by licensed pharmacists and are regulated by state boards of pharmacy and the FDA regarding purity and operations. While the specific compounded mixture itself is not FDA-approved, the individual components must be approved drugs or listed on the FDA’s bulk pharmacy list. They are often used to create specialized topical creams or complex mixtures for specific patient needs, such as neuropathic pain treatments.
Rudolph Diesel’s Mysterious Death
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(01:21:48)
  • Key Takeaway: The most likely cause of Rudolph Diesel’s death in 1913 was suicide due to bankruptcy, despite conspiracy theories suggesting assassination by Germany or Rockefeller.
  • Summary: Rudolph Diesel, inventor of the compression-ignition engine, vanished from a ship in 1913 and was found drowned; historians favor suicide due to his recent bankruptcy. A popular conspiracy theory suggests Germany had him killed to prevent him from selling technology to England, while another posits Rockefeller murdered him to protect gasoline interests. The Rockefeller theory is illogical because the diesel engine was still a niche technology not yet competing with gasoline cars.
Early Automotive Technology Competition
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(01:28:58)
  • Key Takeaway: The dominance of gasoline cars over electric and steam vehicles was primarily due to superior infrastructure for fuel distribution, not inherent technological superiority.
  • Summary: Early electric cars were viable for city driving, but the lack of water infrastructure hampered steam engines, and gasoline infrastructure was built out first. Henry Ford chose to mass-produce gasoline cars after a delay in receiving suitable batteries from Thomas Edison for his electric car design. This infrastructure advantage, coupled with Ford’s decision, cemented gasoline’s dominance over early electric vehicle adoption.
Astronomy News for Science or Fiction
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(01:31:56)
  • Key Takeaway: The existence of four Mars-sized planets orbiting Barnard Star, the closest single-star system, was confirmed science, while claims of nucleic acids on Mars were fiction.
  • Summary: The panel correctly identified the discovery of four Mars-sized planets orbiting Barnard Star (six light-years away) as true, noting that this close, single-star system is ideal for wobble method detection. The finding that NASA’s Curiosity rover discovered simple nucleic acids on Mars was the fiction, although organic chemistry and carbon atoms have been confirmed. The true finding regarding Mars is evidence of ancient life ingredients, not confirmed nucleic acids.
Skeptical Quote of the Week
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(01:43:15)
  • Key Takeaway: A quote from 2 Timothy 4:3-4 warns that people will seek teachers who please them by telling them only what they want to hear, turning away from truth.
  • Summary: The quote highlights the human tendency to seek confirmation bias over difficult truths, stating people will look for teachers who tell them only what they are itching to hear. This tendency causes them to turn away from truth and listen to senseless stories. The hosts noted that while scripture contains such nuggets of wisdom, they often fail to lead to correct scientific conclusions.