INLAND FISHES OF CALIFORNIA
Chapter One
Herrings, Clupeidae
If sheer number of individuals is the criterion for success,
herrings are one of the most successful families of fishes in
the world. Early in the history of teleost evolution, they
achieved plankton-feeding specializations that have allowed
them to remain abundant. Herrings have highly protractile
jaws and long, fine gill rakers for picking and filtering plankton.
Their scales are cycloid, deciduous, and silvery, reflecting
light like miniature mirrors to confuse predators. Their
bodies are muscular yet deepened by a sharp keel on the
belly. The keel eliminates the faint belly shadow most fishes
have when seen from below, thus increasing the difficulty
predators have in picking out individuals from a shoal. Indeed,
most morphological specializations of the Clupeidae
enable them to function in the huge schools in which they
are typically found.
Although usually thought of as marine, herrings are also
successful as anadromous and freshwater fishes. Thanks to
humans, the ranges of ... read full excerpt from: Our Overweight Children: What Parents, Schools, and Communities Can Do to Control the Fatness Epidemic ebook
