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    Living on an island can have stranger effects. On Flores in Indonesia, extinct elephants weighed no more than a large hog, but rats grew as big as cats. These are examples of the island effect, which holds that when food and predators are scarce, big animals shrink and little ones grow. Still, no one is sure whether the same rule explains the most famous example of dwarfing on Flores: the odd extinct hominin called the hobbit, which lived 60,000 to 100, 000 years ago and stood about a meter tall.
    Now, genetic evidence from modern pygmies or unusually short people on Flores-who are unrelated to the hobbit-confirm that humans, too, are subject to so-called island dwarfing. Flores pygmies differ from their closest relatives on New Guinea and in East Asia in carrying more gene variants that promote short stature.
    To explore the pygmies' ancestry, a team of reserachers studied the Rampasasa pgymies of Flores, who were on an average just 145 centimeters tall. They gathered spit and blood from 32 people and analyzed their health histories. The team found no trace of arc;haic DNA that could be from the hobbit. Instead, the pgymies were most closely related to other East Asians.. The DNA suggest that their ancestors came to Flores in several waves: in the past 50,000 years or so, when modern human first reached Melanesia; and in the past 5000 years, when settlers came from both East Asia and New Guinea.
    The DNA also reflects an environmental shift. It suggests the pgymies' ancestors underwent a big shift in diet after reaching Flores, perhaps eating pgymiy elephants or matine foods. They pgymies' DNA is also rich in alleles that are linked to short stature. Other East Asia have the same alleles, but at much lower frequencies.
    The discovery fits with a recent study suggesting evolution was also in favor of short stature in people on the Andaman Islands. Such selection on island boosts the theory that the hobbit, too, was once a taller species, who dwindled in height over millennia on Flores.

Source: Indonesia, Forum Tentor. The King Bedah Kisi-Kisi SBMPTN TPS 2022 dan UM Mandiri. Yogyakarta: Penerbit Forum Edukasi.

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