FISH
Fish were the first animals with backbones to appear on Earth, more than 500 million years ago. They have since evolved into a wonderful variety of forms. From powerful sharks to delicate seahorses, fish now make up more than half of all vertebrate species. Most fish live in the salty oceans, but many fishes live in freshwater lakes and rivers. A few, such as salmon, are able to live in both.
- RAY Closely related to sharks, with skeletons made of cartilage, rays are flattened fish that swim by using their pectoral (side) fins like wings. They live on the seabed, hunting smaller fish and shellfish.
- BOXFISH The curious boxfish are named for their box-like defensive armour, formed from thick, fused scales. This prevents all body movement, so the fish swim by using their small fins like oars.
- FORCEPS FISH A type of butterfly-fish that lives on the coral reefs of the Indian and Pacific oceans, the forceps fish has a highly elongated snout with a very small mouth at the tip. The fish uses this to pick tiny animals from coral crevices, and from the spines of sea urchins.
- SEAHORSE These strange fish owe their name to their horse-like heads. They live in shallow seas, where they cling to marine plants with their tails. The male “incubates” the female’s eggs in a pouch on his belly.
- PUFFERFISH Pufferfish defend themselves by inflating their bodies with water so they are hard for predators to swallow. Some species have sharp spines that add to the effect, and many of their internal organs contain lethal poisons.
- SALMON Big, powerful salmon spend most of their lives at sea, but swim upstream to the shallow rivers with gravelly bottoms where they breed. They have adaptations that allow them to move between fresh and salt water.
- CARP Able to live in water that has very little oxygen, carp are well equipped for life in warm, still lakes and ponds. They feed by using their extendible jaws to root around on the bottom for small animals and aquatic plants.
- VELVET CICHLID Better known by its common name, Oscar, this species lives in slow-flowing South American rivers and digs in the riverbeds for small animals such as worms and freshwater shrimps. There are currently 1,721 species of cichlids known.
- STICKLEBACK This fish gets its name from the sharp spines on its back. It lives in ponds, rivers, and lakes, and some shallow seas. In spring, the male makes a nest of plant fibre, and does a dance to attract females to lay their eggs.
- PIKE This powerful hunter lives in lakes and slow-flowing rivers throughout Europe, northern Asia, and North America. Pike hunt fish and waterbirds by lying in wait among aquatic plants and darting out to seize victims.
- PIRANHA Notorious for its sharp teeth, this South American predator mainly preys on other fishes, but may strip the meat from larger carcasses of dead animals.
Picture Credit : Google
