Although the body shapes of the over 140 species of jacks and pompanos range from torpedo-like to nearly plate-like, all are fast swimming predators. This is reflected in their deeply forked tails and narrow caudal peduncles; the fine, cycloid scales; the deeply sloping heads with large eyes and mouth; and, usually, the laterally compressed bodies. Carangids range in color from silvery to metallic blue or green to bright yellow or gold. Adult size ranges from about 25 cm to 2 m. Most jacks are schooling fish that feed by making rapid, slashing attacks at schools of smaller fish, especially herrings and anchovies.