Zoology is the scientific study of animals. Its studies include the structure, embryology, classification, habits, and distribution of all animals, both living and extinct, and how they interact with their ecosystems. Zoology is one of the primary branches of biology. The term is derived from Ancient Greek ζῷον, zōion ('animal'), and λόγος, logos.
Lachesis is a genus of venomous pit vipers in the family Viperidae. Member species are found in forested areas of the Neotropics. The generic name refers to one of the Three Fates, Lachesis, who determined the length of the thread of life. Four species are currently recognized as being valid.
The eastern copperhead, also known simply as the copperhead, is a species of venomous snake, a pit viper, endemic to eastern North America; it is a member of the subfamily Crotalinae in the family Viperidae.
Squamata is the largest order of reptiles, comprising lizards, snakes, and amphisbaenians, which are collectively known as squamates or scaled reptiles. With over 10,900 species, it is also the second-largest order of extant (living) vertebrates, after the perciform fish. Members of the order are distinguished by their skins, which bear horny scales or shields, and must periodically engage in molting. They also possess movable quadrate bones, making possible movement of the upper jaw relative to the neurocranium. This is particularly visible in snakes, which are able to open their mouths very wide to accommodate comparatively large prey. Squamates are the most variably sized living reptiles, ranging from the 16 mm (0.63 in) dwarf gecko to the 6.5 m (21 ft) Reticulated python. The now-extinct mosasaurs reached lengths over 14 m (46 ft).
Crotalus cerastes, known as the sidewinder, horned rattlesnake or sidewinder rattlesnake, is a pit viper species belonging to the genus Crotalus, and is found in the desert regions of the Southwestern United States and northwestern Mexico. Like all other pit vipers, it is venomous. Three subspecies are currently recognized.
Agkistrodon piscivorus is a species of pit viper in the subfamily Crotalinae of the family Viperidae. It is one of the world's few semiaquatic vipers, and is native to the Southeastern United States. As an adult, it is large and capable of delivering a painful and potentially fatal bite. When threatened, it may respond by coiling its body and displaying its fangs. Individuals may bite when feeling threatened or being handled in any way. It tends to be found in or near water, particularly in slow-moving and shallow lakes, streams, and marshes. It is a capable swimmer, and like several species of snakes, is known to occasionally enter bays and estuaries and swim between barrier islands and the mainland.
Agkistrodon is a genus of venomous pit vipers commonly known as American moccasins. The genus is endemic to North America, ranging from the Southern United States to northern Costa Rica. Eight species are currently recognized, all of them monotypic and closely related. Common names include: cottonmouths, copperheads, and cantils.
Crotalus willardi is a venomous pit viper species found in the southwestern United States and Mexico. This snake is found mainly in the "sky island" region. The IUCN reports this snake's conservation status as being of Least Concern. It is the official state reptile of Arizona.
Crotalus viridis is a venomous pit viper species native to the western United States, southwestern Canada, and northern Mexico. Currently, two subspecies are recognized, including the prairie rattlesnake, the nominate subspecies, and the Hopi rattlesnake.
Crotalus oreganus abyssus is a venomous pit viper subspecies found only in the U.S. states of Arizona and Utah.
Parthenogenesis is a natural form of asexual reproduction in which growth and development of embryos occur in a gamete without combining with another gamete. In animals, parthenogenesis means development of an embryo from an unfertilized egg cell. In plants, parthenogenesis is a component process of apomixis. In algae, parthenogenesis can mean the development of an embryo from either an individual sperm or an individual egg.
Agkistrodon howardgloydi is a species of venomous snake, a pit viper (Crotalinae), that is endemic to Central America. It is most commonly called castellana,but it has also been called the southern cantil, Gloyd's moccasin, and a number of other colloquial names. It is a rare species with a relatively small geographic distribution in the tropical dry forest on the Pacific coast of Honduras, Nicaragua, and extreme northwest Costa Rica. Agkistrodon howardgloydi is a stout, medium-sized snake with a maximum length of 96 cm. It is a viviparous species, with female giving birth in the rainy season from May to August. No clinical reports on envenomation had been published, but laboratory texts and analysis indicate the venom is highly toxic and similar to its close relative Agkistrodon bilineatus, and potentially lethal.
The small-scaled burrowing asp is a species of atractaspidid snake from West Africa.
Caudal luring is a form of aggressive mimicry characterized by the waving or wriggling of the predator's tail to attract prey. This movement attracts small animals who mistake the tail for a small worm or other small animal. When the animal approaches to prey on the worm-like tail, the predator will strike. This behavior has been recorded in snakes, sharks, and eels.
Robert D. Martin is a British-born biological anthropologist who is currently an Emeritus Curator at The Field Museum of Natural History in Chicago, Illinois. He is also an adjunct professor at University of Chicago, Northwestern University, and University of Illinois Chicago. His research spans the fields of anthropology, evolutionary biology and human reproductive biology. Additionally, he writes a blog on human reproduction for Psychology Today.
David Pafford Crews is the Ashbel Smith Professor of Zoology and Psychology at the University of Texas at Austin. He has been a pioneer in several areas of reproductive biology, including evolution of sexual behavior and differentiation, neural and phenotypic plasticity, and the role of endocrine disruptors on brain and behavior.
Tail vibration is a common behavior in some snakes where the tail is vibrated rapidly as a defensive response to a potential predator. Tail vibration should not be confused with where the tail is twitched in order to attract prey. While rattlesnakes are perhaps the most famous group of snakes to exhibit tail vibration behavior, many other snake groups—particularly those in the Colubridae and Viperidae families—are known to vibrate tails when feeling threatened.
Ellen D. Ketterson is an American evolutionary biologist, behavioral ecologist, neuroendocrinologist and ornithologist best known for her experimental approach to the study of life-history trade-offs in a songbird, the Dark-eyed Junco. She is currently a Distinguished Professor of Biology, Director of the Environmental Resilience Institute, and affiliate professor in Cognitive Science, Gender Studies, Integrative Study of Animal Behavior, and Neuroscience at Indiana University.
The winner and loser effect is an aggression phenomenon in which the winner effect is the increased probability that an animal will win future aggressive interactions after experiencing previous wins, while the loser effect is the increased probability that an animal will lose future aggressive interactions after experiencing previous losses. Overall these effects can either increase or decrease an animals aggressive behaviour, depending on what effect affects the species of concern. Animals such as Agkistrodon contortrix, Rivulus marmoratus, and Sula nebouxii show either both or one of these effects.
In evolutionary biology, mimicry in vertebrates is mimicry by a vertebrate of some model, deceiving some other animal, the dupe. Mimicry differs from camouflage as it is meant to be seen, while animals use camouflage to remain hidden. Visual, olfactory, auditory, biochemical, and behavioral modalities of mimicry have been documented in vertebrates.
