Blood-sucking animals are animals that feed on the blood of other organisms. These animals usually pierce the host's skin through their mouthparts or other special organs, and then suck out the host's blood. Blood-sucking animals are diverse, including insects such as mosquitoes, fleas, lice,...
According to EurekAlert!: A study explores the genetic basis for the origin of paired appendages in vertebrate evolution. Jawless vertebrates possess two sets of appendages, such as pectoral and ventral fins, while living jawless fish, such as lampreys and hagfish, lack paired fins. However,...
Lampreys look very much like ordinary eels. They have a slender body with exposed skin without scales. There is a long dorsal fin on its back, which extends back to the tail end and surrounds the tail to form a caudal fin. In addition, it has no other parts on its body. No other fins are pres...