Ultrasound is sound with frequencies greater than 20 kilohertz. This frequency is the approximate upper audible limit of human hearing in healthy young adults. The physical principles of acoustic waves apply to any frequency range, including ultrasound. Ultrasonic devices operate with frequencies from 20 kHz up to several gigahertz.
Moths are a group of insects that includes all members of the order Lepidoptera that are not butterflies. They were previously classified as suborder Heterocera, but the group is paraphyletic with respect to butterflies and neither subordinate taxa are used in modern classifications. Moths make up the vast majority of the order. There are thought to be approximately 160,000 species of moth, many of which have yet to be described. Most species of moth are nocturnal, although there are also crepuscular and diurnal species.
Echolocation, also called bio sonar, is a biological active sonar used by several animal groups, both in the air and underwater. Echolocating animals emit calls and listen to the echoes of those calls that return from various objects near them. They use these echoes to locate and identify the objects. Echolocation is used for navigation, foraging, and hunting prey.
The Arctiinae are a large and diverse subfamily of moths with around 11,000 species found all over the world, including 6,000 neotropical species. This subfamily includes the groups commonly known as tiger moths, which usually have bright colours, footmen, which are usually much drabber, lichen moths, and wasp moths. Many species have "hairy" caterpillars that are popularly known as woolly bears or woolly worms. The scientific name Arctiinae refers to this hairiness. Some species within the Arctiinae have the word "tussock"' in their common names because they have been misidentified as members of the Lymantriinae subfamily based on the characteristics of the larvae.
The Mexican free-tailed bat or Brazilian free-tailed bat is a medium-sized bat native to the Americas, so named because its tail can be almost half its total length and is not attached to its uropatagium. It has been claimed to have the fastest horizontal speed of any animal, reaching top ground speeds over 99 mph (160 km/h). It also flies the highest among bats, at altitudes around 3,300 m (10,800 ft).
In evolutionary biology, an evolutionary arms race is an ongoing struggle between competing sets of co-evolving genes, phenotypic and behavioral traits that develop escalating adaptations and counter-adaptations against each other, resembling the geopolitical concept of an arms race. These are often described as examples of positive feedback. The co-evolving gene sets may be in different species, as in an evolutionary arms race between a predator species and its prey, or a parasite and its host. Alternatively, the arms race may be between members of the same species, as in the manipulation/sales resistance model of communication or as in runaway evolution or Red Queen effects. One example of an evolutionary arms race is in sexual conflict between the sexes, often described with the term Fisherian runaway. Thierry Lodé emphasized the role of such antagonistic interactions in evolution leading to character displacements and antagonistic coevolution.
The lesser horseshoe bat is a type of small European and North African insectivorous bat, related to its larger cousin, the greater horseshoe bat. As with all horseshoe bats, the species gets its name from its distinctive horseshoe-shaped noseleaf.
The brown long-eared bat or common long-eared bat is a small Eurasian insectivorous bat. It has distinctive ears, long and with a distinctive fold. It is extremely similar to the much rarer grey long-eared bat which was only validated as a distinct species in the 1960s. An adult brown long-eared bat has a body length of 4.5–4.8 cm, a tail of 4.1–4.6 cm, and a forearm length of 4–4.2 cm. The ears are 3.3–3.9 cm in length, and readily distinguish the long-eared bats from most other bat species. They are relatively slow flyers compared to other bat species.
In ecology, crypsis is the ability of an animal or a plant to avoid observation or detection by other animals. It may be a predation strategy or an antipredator adaptation. Methods include camouflage, nocturnality, subterranean lifestyle and mimicry. Crypsis can involve visual, olfactory or auditory concealment. When it is visual, the term cryptic coloration, effectively a synonym for animal camouflage, is sometimes used, but many different methods of camouflage are employed by animals or plants.
Parnell's mustached bat is an insectivorous bat native to the Americas. It ranges from southern Sonora, Mexico, south to Brazil. It has a wider historical range; fossil specimens have been collected on the island of New Providence in the Bahamas.
The Egyptian fruit bat or Egyptian rousette is a species of megabat that is found in Africa, the Middle East, the Mediterranean, and the Indian subcontinent. It is one of three Rousettus species with an African-Malagasy range, though the only species of its genus found on continental Africa. The common ancestor of the three species colonized the region in the late Pliocene or early Pleistocene. The species is traditionally divided into six subspecies. It is considered a medium-sized megabat, with adults weighing 80–170 g (2.8–6.0 oz) and possessing wingspans of approximately 60 cm (24 in). Individuals are dark brown or grayish brown, with their undersides paler than their backs.
Cycnia tenera, the dogbane tiger moth or delicate cycnia, is a moth in the family Erebidae. It occurs throughout North America, from southern British Columbia to Nova Scotia southwards to Arizona and Florida. The species is distasteful and there is evidence that it emits aposematic ultrasound signals; these may also jam bat echolocation, as the functions are not mutually exclusive.
The greater mouse-eared bat is a European species of bat in the family Vespertilionidae.
The golden-tipped bat is a species of Microchiropteran in the family Vespertilionidae. It is found in Papua New Guinea and in Australia, especially scattered along the eastern part of Australia. The species is considered uncommon, and is listed as endangered in Australia.
Bertholdia is a genus of moths in the family Erebidae.
The tymbal is the corrugated exoskeletal structure used to produce sounds in insects. In male cicadas, the tymbals are membranes in the abdomen, responsible for the characteristic sound produced by the insect. In tiger moths, the tymbals are modified regions of the thorax and produce high-frequency clicks. In lesser wax moths the left and right tymbals emit high-frequency pulses that are used as mating calls.
Bats are flying mammals of the order Chiroptera. With their forelimbs adapted as wings, they are the only mammals capable of true and sustained flight. Bats are more agile in flight than most birds, flying with their very long spread-out digits covered with a thin membrane or patagium. The smallest bat, and arguably the smallest extant mammal, is Kitti's hog-nosed bat, which is 29–34 millimetres in length, 150 mm (6 in) across the wings and 2–2.6 g in mass. The largest bats are the flying foxes, with the giant golden-crowned flying fox reaching a weight of 1.6 kg and having a wingspan of 1.7 m.
Ultrasound avoidance is an escape or avoidance reflex displayed by certain animal species that are preyed upon by echolocating predators. Ultrasound avoidance is known for several groups of insects that have independently evolved mechanisms for ultrasonic hearing. Insects have evolved a variety of ultrasound-sensitive ears based upon a vibrating tympanic membrane tuned to sense the bat's echolocating calls. The ultrasonic hearing is coupled to a motor response that causes evasion of the bat during flight.
Echolocation systems of animals, like human radar systems, are susceptible to interference known as echolocation jamming or sonar jamming. Jamming occurs when non-target sounds interfere with target echoes. Jamming can be purposeful or inadvertent, and can be caused by the echolocation system itself, other echolocating animals, prey, or humans. Echolocating animals have evolved to minimize jamming, however; echolocation avoidance behaviors are not always successful.
Akito Y. Kawahara is an American and Japanese entomologist, scientist, and advocate of nature education, and the son of the modern conceptual artist On Kawara.
