There are many floating villages on the Rhine Lake in Myanmar, which are connected to form a floating island. There are houses, shops, schools, etc. in the villages. The most special one is the floating vegetable gardens. In order to make a better living, the locals gather water plants, duckweed, vines, reeds and other plants on the lake, spread a layer of soil, sprinkle some rotten plants as fertilizer, and plant crops directly on it. The floating island vegetable garden has enough water and soil and fertilizer, which is very suitable for planting vegetables and crops; even if it encounters heavy rain, the rainwater will flow from the island to the lake, and the vegetable garden will rise and fall with the rise and fall of the lake water, and will not be submerged due to the sudden rise of the lake water; more Don't be afraid of drought and no rain, which will cause the plants to dry up.
These vegetable gardens can also be moved, and if you push hard, you can lead the vegetable gardens along. The floating island vegetable garden has also become a local special attraction.
Scientists have discovered the secret of "forever young", which is to be a turtle.
Two studies published July 23 in the journal Science reveal that some cold-blooded animals hardly age, challenging the theory that the body inevitably ages slowly over time.
Penn State wildlife ecologist David Miller, the lead author of one of the papers, and his colleagues collected data from a long-term field study that included 107 groups of 77 wild species, including turtles, snakes, and alligators. and turtle.
They both used a "tag-recapture" method, in which a certain number of individuals were captured and tagged and then tracked for several years to see if they could be found again, in order to estimate mortality.
In addition, they collected data on how many years these animals lived after reaching sexual maturity, and used statistical methods to derive aging rates and longevity, which is the lifespan of 95% of individuals in the population.
"We found some examples of less obvious aging," said lead researcher Beth Reinke, a biologist at Northeastern Illinois University.
Although they had thought it was a turtle-only condition, scientists were also cold-blooded. This phenomenon has been found in species including frogs, toads and crocodiles.
Scientists have long believed that because ectothermic animals rely on external temperatures to regulate their body temperature, they have lower metabolic rates -- aging more slowly than ectothermic animals, which are internally heat-producing and have a higher metabolism.
This relationship applies to mammals. For example, mice have a much faster metabolism than humans and have a much shorter life expectancy than humans.
Surprisingly, however, new research has found that metabolic rate is not the main factor previously thought.
"While some exothermal animals live longer than endothermic animals, there are also some cold-blooded animals that age faster and have shorter lifespans," Miller said.
The study also provides some intriguing clues that may help future research. For example, when the research team looked directly at a species' average body temperature rather than its metabolic rate, they found that warmer reptiles age faster, while the opposite is true in amphibians.
The research supports a theory that animals with protective physiological traits, such as turtle shells, or toxins released by some frogs and salamanders, live longer and age more slowly than animals without them.
Scientists Steven Ostad and Caleb Finch wrote in a review article: "If some species do escape aging, mechanistic studies may reveal the secrets of human health and longevity or Benefit from it.”
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