Friday, July 04, 2025
Flatworms
When a flatworm's head is severed, it can regenerate a new head. The remaining body section, if large enough and containing the necessary stem cells (neoblasts), will regrow the missing parts, including a complete, functional head with a brain and sensory organs. This remarkable ability is a hallmark of flatworms, particularly planarians.
...the new brain can have memories of the old brain, or at least retain learned behaviors from before decapitation.
Research, particularly with planarian flatworms, has shown that if a flatworm is trained to perform a certain task (e.g., associating light with food, or navigating a specific texture), and then its head is severed, the regenerated worm with a brand new brain will often exhibit a "savings" of that learned behavior. This means they either perform the task faster than untrained worms, or show some retained preference for the learned association.
This phenomenon suggests that memories, or at least the underlying changes that lead to learned behaviors, are not solely stored in the brain. Scientists hypothesize that these "memories" might be encoded in other parts of the flatworm's body, perhaps in:
- The peripheral nervous system: The network of nerves throughout the body.
- Epigenetic changes: Modifications to DNA that alter gene expression without changing the DNA sequence itself. These changes could be widespread throughout the worm's cells.
- Non-neural tissues: Some evidence suggests that cells outside the nervous system might play a role in storing and transmitting this information to the regenerating brain.
The exact mechanisms by which these memories are stored outside the brain and then "imprinted" onto the new brain during regeneration are still a subject of active research, but it's a truly remarkable example of biological information storage and transfer.
Thursday, July 03, 2025
Wednesday, July 02, 2025
Five!
NOAA: How many oceans are there?
Historically, there are four named oceans: the Atlantic, Pacific, Indian, and Arctic. However, most countries - including the United States - now recognize the Southern (Antarctic) as the fifth ocean.Hawaii
"Hawaii has lost two-thirds of its native birds since humans arrived, about sixteen hundred years ago, many of them disappearing after the introduction of avian malaria, likely from larval mosquitoes in the drinking water of whaling ships." Joe Roman
Kapu
From Ai Gemini:
The Hawaiian concept of kapu refers to a system of ancient laws and regulations that dictated what was sacred, forbidden, or off-limits.
It encompassed a comprehensive code of conduct governing everything from religious practices and social roles to daily activities and resource management, often with severe penalties for violations. The word "kapu" is closely related to the Polynesian concept of "tabu" or "taboo."
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The Ultimate Guide to Understanding Kapu in Hawaiian Culture By Dimple
Commoners were often restricted in their daily activities; for instance, certain types of fish and fruits were deemed exclusive to the ali’i, and areas for fishing and agriculture were sharply delineated by social rank. The system extended its reach into warfare, prescribing who could fight and the sacred rituals that must precede battle.
