Atavist

Courtesy of Dictionary.com, an atavism is defined as follows:


 * atavism


 * [at-uh-viz- uh  m]


 * noun


 * 1. Biology.


 * a. the reappearance in an individual of characteristics of some remote ancestor that have been absent in intervening generations.


 * b. an individual embodying such a reversion.


 * 2. reversion to an earlier type; throwback.

Origin of atavism


 * 1825-35; < Latin atav (us) remote ancestor (at-, akin to atta familiar name for a grandfather + avus grandfather, forefather) + -ism

Related forms


 * atavist, noun

According to "Rescue Sirens"' unique mermaid mythology, merfolk existed before human beings — in fact, they represent our species' very origin. From the beginning of time, mermaids and mermen were able to "make legs" indistinguishable from our own and walk around on shore, where they bred, gave birth in special birthing coves, and simply explored the vast expanses of wild land.

There was a catch, though (isn't there always?): after more than a day away from the ocean, legged merfolk would start to feel ill, and if they went for three full days without "turning tail" and submerging in water from head to fin-tip, their specialized lungs would dry up and they would lose their ability to change from legs to tail. Forever.

In other words, they became human.

Across the globe, merfolk were trapped on land often enough — due to losing their way, natural disasters, illness or injury, and even treachery — that the resulting small bands of human beings were able to sustain and eventually grow their population (although the offspring of human/human pairings lacked from birth the capacities to "turn tail" and breathe underwater). These humans were watched over when they went near the water by the mermaids and mermen still living in the ocean, and merfolk observe that ancient vow to protect their landbound brethren to this day; that's the role of a Rescue Siren.

But sometimes, once in a very long while, a human being is born with the ability locked within them to change their legs into a tail (and back again) as well as to breathe water, just like humankind's merfolk ancestors. This genetic throwback is known amongst merfolk as an Atavist. It is the search for just such a human by the Rescue Sirens of Miami Beach that forms the basis for the first novel, "Rescue Sirens: The Search for the Atavist."