Poems and Thoughts    by Frank Maurer

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The Labyrinth. Fish have gills,Silly: How else would they breathe? Well, because of evolution through natural selection, A group of fish (there are many other examples) Inhabiting the Vietnam, Laos, Malaysia area are the Bettas. Bettas were originally found in Thailand. They are among the oldest domesticated fish species in the world, Having been owned as pets for more than 1000 years! They survive in small puddles of water, in rice fields, and ditches. Because of the uncertain fluctuating oxygen supply, They have evolved a structure at the bony base of the gill, Called a labyrinth, which allows not only gill breathing, But also the intake of air, by gulping, this interacting within the labyrinth, Supplementing the often low oxygen content in the surrounding water. The labyrinth contains plates with a myriad of oxygen absorbing blood vessels Which gather inhaled air now trapped inside a group of folds And then absorbed into the main bloodstream. Bettas are obligate air breathers in that they occasionally must take in oxygen from the air. The other group of labyrinth fish are facultative air breathers, Which only breathe at the surface when running low on oxygen. Bettas breathe using their labyrinth organ, day and night, So they prefer sleeping under large plants near the water's surface And thus do not need to exert extra energy to rise to the top for a quick gulp. Interestingly, they use this organ to create 'bubble nests' at the surface. The males blow bubbles to form one of these nests as part of their reproductive process, But even single males will make a bubble nest, if content in their space! Just another fascinating creature to get to know and this is why Natural history study makes one an ever-more interesting person.      Try it! Frank Maurer 11 July 2023 1615 Hours.