Growing up to 3m (10 ft) in length the Alligator gar is the largest species of gar and one of the largest freshwater fish in North America. The primitive fish is able to withstand low oxygen conditions as it is able to breath atmospheric air using a modified swim bladder.
The fish is an ambush predator, lying still in the water as if it were a floating log. Unsuspecting prey, which consists of other fish, small mammals and birds, unknowingly approach the gar. When in striking range, the gar lunges forward, penetrating its prey with its double row of sharp teeth.
The alligator gar has been historically classified as a nuisance, and was indiscriminately hunted in much of its range. As a result, much of its range and population sizes have been reduced. Nowadays, there are projects to help monitor these fish and help protect them against further endangerment.
Goldfish have been selectively bred for hundreds of years, resulting in a wide variation in morphology. The popular ornamental fish was first domesticated from wild carp in China, where orange mutations of the normally silver fish were recorded in the Jin Dynasty (265 - 420).
In the Tang dynasty (618 - 920), carp were commonly kept in ornamental ponds and were selectively bred for a gold mutation. By the Song Dynasty (920 - 1279), the domestication of goldfish was firmly established.
Today, there are about 300 distinct breeds recognised in China. Some popular varieties include features such as the bubble eye, telescope eyes, fancy tails and a compressed body. Many of these features provide significant disadvantage for the fish and as such, specialist care is needed to successfully raise and breed them.