Science and Technology

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Striped Bark Scorpions

aka: Centruroides vittatus
The striped bark scorpion, Centruroides vittatus, is the only scorpion species recorded from Arkansas, where it is most abundant in the western part of the state. It is the most widely distributed scorpion species in the United States, having been recorded from Missouri, Arkansas, and Louisiana west to eastern Colorado and New Mexico and south to northeastern Mexico. The front body region, which bears the yellowish-brown pedipalps (pincers) and legs below, has a somewhat triangular median dark spot on top pointing backward and extending beyond the eyes. The wide body region that follows has a distinctive pair of broad, dark, longitudinal bands on top. The slender tail-like postabdomen is uniformly yellowish brown, except for the tip of the stinger, which …

Sturgeons

Sturgeons (primitive Acipenseriform) are an ancient group of fishes dating back to the Triassic Period some 245 to 208 million years ago. True sturgeons appear in the fossil record during the Upper Cretaceous (101 to 66 million years ago). There are about twenty-five species of sturgeons, and all belong to the Family Acipenseridae, Order Acipenseriformes. Sturgeons can be found in subtropical, temperate, and sub-Arctic rivers, lakes, and coastlines of North America, with the greatest diversity in Eurasia. In North America, there are eight species that range along the Atlantic Coast from the Gulf of Mexico to Newfoundland, as well as along the West Coast in major rivers from California and Idaho to British Columbia, Canada. The family contains four genera …

Suckers

aka: Catostomid Fishes
Suckers belong to the Family Catostomidae, Order Cypriniformes, and Class Actinopterygii. There are about seventy-two species and thirteen extant genera of these benthic (bottom-dwelling) freshwater fishes. In Arkansas, there are eighteen species in eight genera. Suckers are Holarctic in distribution and primarily native to North America north of Mexico, but the longnose sucker (Catostomus catostomus) occurs in both North America and northeastern Siberia from Alaska, and the Asiatic Sucker (Myxocyprinus asiaticus) is found in the Yangtze River basin in China. Sucker-like fossils are known from Eocene epoch (56 to 33.9 million years ago) deposits from central Asia, and the fossil genus Amyzon, with Ictiobus and Myxocyprinus affinities, occurs in middle Eocene and Oligocene Epoch (33.9 to 23 million years ago) …

Symphylans

aka: Glasshouse Symphylans
aka: Garden Centipedes
aka: Pseudocentipedes
Symphylans belong to the Phylum Arthropoda, Subphylum Labiata, Superclass Myriapoda, and Class Symphyla. About 200 species of symphylans are known worldwide, predominantly in the tropics. There are two families: Scutigerellidae with five genera and about 128 species, and Scolopendrellidae containing nine genera and approximately seventy-three species. There are few reports of symphylans in Arkansas, aside from a new endemic scutigerellid species described in 1992 in Polk County. Many taxa are yet to be discovered and described in the state. The fossil record of symphylans is poorly known; only five species have been recorded, all placed within living genera. They are ancestral arthropods dating back to the early Silurian approximately 430 million years ago, although the only fossil symphylans are known …

Tarantulas

Tarantulas are the largest spiders in Arkansas and are among the most recognizable. Tarantulas are relative newcomers to Arkansas, having arrived in the state about 8,000 years ago. At that time, the climate of North America was much warmer and drier than it is today. Because of higher temperatures and lower amounts of rainfall, habitats more typical of the southwestern United States and the Great Plains expanded eastward into Arkansas and Missouri. Along with drier habitats came many of the animals associated with them, such as tarantulas and scorpions. As the climate became cooler and wetter about 4,000 years ago, these species did not retreat west. Instead, they became isolated within suitable patches of open, dry habitat surrounded by increasing …

Tardigrades

aka: Water Bears
aka: Moss Piglets
Tardigrades (sometimes called water bears or moss piglets) are microscopic members of the Phylum Tardigrada, numbering more than sixty-seven subspecies, 1,018 species, four subgenera, 105 genera, fifteen subfamilies, twenty families, five orders, and three classes. Of these, there are fifty-four genera and 380 species known from the Americas, 245 species from the Nearctic ecozone, and 251 in the Neotropical ecozone. Several species of tardigrades can be found in Arkansas. Discovered in 1773 by the German entomologist and pastor Johann August Ephraim Goeze (1731–1793), they were nicknamed “water bears” because of their plump, bear-like appearance; legs with claws; and slow, lumbering gait. The name Tardigrada (“slow steppers”) was given in 1777 by the Italian Catholic priest, biologist, and physiologist Lazzaro Spallanzani …

Temperate Basses

aka: Moronids
The temperate basses are freshwater, brackish water, and marine species belonging to the Order Perciformes and Family Moronidae. They are represented by two genera and six species—the North American and northern African Morone (four species) and European Dicentrarchus (two species). In North America, two popular freshwater game fish species, white bass (Morone chrysops) and yellow bass (M. mississippiensis), are native, whereas two others, the anadromous striped bass (M. saxatilis) and brackish water white perch (M. americana), have been successfully introduced into several U.S. states. In Arkansas, M. chrysops, M. mississippiensis, M. saxatilis and, rarely, M. americana are found in various watersheds. In addition, hybrid M. saxatilis × M. chrysops have been cultured and stocked in several Arkansas reservoirs. Morphologically, in …

Termites

aka: Isopterans
Termites belong to the Phylum Arthropoda, Class Insecta, Infraorder Isoptera, and Order Blattodea. They were formerly placed in a separate order (Isoptera) from the cockroaches (Blattodea), but Isoptera is currently classified at the taxonomic rank of infraorder. About 3,106 species are currently described within twelve families, with a few hundred more to still be described. There are several species of termites in Arkansas. Termites are among the most successful groups of insects on Earth, colonizing all continents except Antarctica. Comparatively speaking, the diversity of termite species is rather low in North America and Europe (fifty species are known from North America, and only ten species occur in Europe), but it is higher in South America, where over 400 species are …

Thomas, Ruth Harris

Ruth Harris Thomas was a highly regarded amateur ornithologist whose column on birding in Arkansas was published by the Arkansas Gazette for about forty years. Her column not only documented area birds, but it also contributed to a growing appreciation for birds, birding, and habitat conservation. Ruth Harris was born in Kentucky on August 25, 1900, to Charles O. Harris and Columbia B. Cox Harris. She had two brothers. Majoring in English and journalism, Harris graduated from Louisiana State University in 1923, where she also edited the student newspaper. She moved to Little Rock (Pulaski County) in the autumn of 1923 to work as a reporter for the Arkansas Gazette newspaper. In 1927, she married Maine native Stanley Powers Rowland …

Thrips

Thrips belong to the Phylum Arthropoda, Class Insecta, and Order Thysanoptera. They are minute (most are less than 1 mm long), slender insects with fringed wings and distinctive asymmetrical mouthparts. There are currently over 7,700 species-groups of recognized thrips, grouped into 780 extant and fifty-eight fossil genera. The traditional classification of the order recognizes nine families for extant species (plus five fossil families), with two subfamilies in the Phlaeothripidae (the only family in suborder Tubulifera) and four subfamilies in the Thripidae (one of eight families comprising suborder Terebrantia). The earliest recorded mention of thrips is from the seventeenth century and was a sketch made in 1691 by an Italian Jesuit scholar, Philippo Bonanni (1628‒1723). In 1744, the Swedish entomologist Baron …

Ticks

Ticks belong to the phylum Arthropoda, class Arachnida, subclass Acari, suborder Parasitiformes, and order Ixodida (Metastigmata), which includes almost 900 recognized species. There are three families: Ixodidae, or the “hard” ticks (approximately 700 species); Argasidae, or the “soft” ticks (approximately 200 species); and Nuttalliellidae, containing only a single species, Nuttalliella namaqua, a tick found only in southern Africa. In Arkansas, nine genera and a total of nineteen species (three argasids and sixteen ixodids) are known. Another species, Rhipicephalus (Boophilus) annulatus, has been extirpated from Arkansas. Ticks are a highly specialized group of obligate, bloodsucking, nonpermanent ectoparasitic arthropods of vertebrates (mostly on reptiles, birds, and mammals) and are distributed throughout the world. In addition to being irritating to hosts and causing …

Topminnows

aka: Fundulids
aka: Killifishes
Topminnows belong to the Family Fundulidae, Order Cypriniformes, and Class Actinopterygii. This family also includes some North American killifishes. There are approximately forty-four to forty-six species that are found in the lowlands of North and Central America from southeastern Canada to the Yucatan Peninsula of Mexico, including the Mississippi River drainage, and the islands of Bermuda and Cuba. Most (forty species) of topminnows belong to the genus Fundulus, and others are included in the genera Lucania (three species) and Leptolucania (a single species). The Family Fundulidae is a paraphyletic grouping of members of genera Fundulus and Lucania. There are six species of topminnows found in Arkansas. Topminnows occur in both freshwater and marine waters as well as brackish environments. They …

Tornado Outbreak of 1952

The tornado season of 1952 was a particularly eventful one throughout the state. Twenty-six tornadoes were reported to have touched down in Arkansas from January to November that year. While twenty-six is well below the modern average of about thirty-nine tornadoes per year in Arkansas, an unusually large number of these storms in 1952 were EF-3 and stronger on the Enhanced Fujita Scale used to rate the strength of tornadoes (the ratings go from EF-0 to EF-5). Of the twenty-six tornadoes in this outbreak, at least five were rated EF-4. Among these tornadoes, the most deadly and most widely reported was the March 21, 1952, EF-4 tornado that struck White County on March 21. Over the course of the year, …

Tornado Outbreak of March 1, 1997

The tornado outbreak of March 1, 1997, was one of the deadliest in the history of the state of Arkansas. Sixteen tornadoes tracked across the state, killing twenty-five Arkansans. Several of the tornadoes had unusually long tracks, traveling between fifty and seventy-five miles. There was also a higher than statistically expected number of tornadoes of F3 strength or higher—that is, tornadoes with wind speeds in excess of 158 miles per hour. Of the sixteen tornadoes, four were responsible for all fatalities in the state, as well as much of the property damage. All sixteen tornadoes were produced by four supercell thunderstorms, with the four killer tornadoes being spawned from two such storms that formed ahead of a cold front. The …

Tornadoes

Tornadoes—destructive, violently spinning vortices of air extending from high within severe thunderstorms to the surface of the earth—are more common in the United States than anywhere else on the planet. They are particularly prevalent in the area known as “Tornado Alley,” where the proper ingredients come together: a combination of warm, moist air from the Gulf of Mexico pulled northward by storm systems dragging strong continental cold air from Canada. While Arkansas is not normally included on maps of the infamous Tornado Alley, which is usually considered to stretch from north Texas northward through Oklahoma, Kansas, and Nebraska, the state has suffered many devastating tornado outbreaks. In January 1999, Arkansas recorded the most tornadoes on any individual January day in …

Trees

When European explorers first came to Arkansas in the sixteenth century, they found the vast majority of the state covered by some type of forest or woodland. In general, the upland areas of the state were covered by short-leaf pine/oak/hickory forests in areas underlain by acidic rocks (primarily sandstone and chert) and by oak/hickory forests in areas underlain by neutral to calcareous rocks (primarily limestone and dolomite). Lowland areas of eastern and southern Arkansas were covered primarily by bottomland hardwood forests, with bald-cypress/water-tupelo swamps in the wettest areas. The Gulf Coastal Plain of southern Arkansas was covered by a mix of forest types, with loblolly and/or short-leaf pine dominant in many areas. Within these general forest types were hundreds of …

Trematodes

aka: Flatworms
aka: Flukes
Trematodes (flukes) include parasitic flatworms belonging to the phylum Platyhelminthes, class Trematoda, and subclasses Aspidogastrea (two orders, four families) and Digenea (ten orders, more than seventy-two families). The class numbers between 18,000 and 24,000 species; they are found primarily in a variety of animals, including humans and other vertebrates. Modern phylogenetic analysis reveals that the worms of class Monogenoidea (monogenetic flukes) are no longer included within the Trematoda and are more closely related to tapeworms. The modern mobility of human beings, combined with the international transportation of animals and foodstuffs that can be infected, means that diagnoses can occur well outside the areas where trematode species are endemic. However, while trematodes do occur in Arkansas, they do not pose a …

Tropical Cyclones

aka: Tropical Storms and Depressions
As defined by the National Hurricane Center, a tropical cyclone is a “rotating, organized system of clouds and thunderstorms that originates over tropical or subtropical waters and has a closed low-level circulation.” Types of tropical cyclones are classified in terms of wind speed: A tropical depression is a tropical cyclone with maximum sustained winds of 38 miles per hour (mph) or lower. A tropical storm is a tropical cyclone with maximum sustained winds of 39 to 73 mph. A hurricane is a tropical cyclone with maximum sustained winds of 74 mph or higher. A major hurricane is tropical cyclone with maximum sustained winds of 111 mph or higher. Given the landlocked, central location of the state of Arkansas, it may …

Turpentine Creek Wildlife Refuge

Turpentine Creek Wildlife Refuge near Eureka Springs (Carroll County) is a 501(c)(3) nonprofit organization providing lifetime homes for abandoned, abused, and neglected big cats and other endangered wildlife. With over 450 acres and more than 120 exotic cats, the refuge is one of the largest big cat sanctuaries in North America licensed by the U.S. Department of Agriculture (USDA). The sanctuary is rated a “Must See” attraction by the Arkansas Department of Parks and Tourism and is one of the most popular destinations in the Eureka Springs area. Don Jackson, a former employee of the Dallas Zoo, along with his wife, Hilda, and their daughter, Tanya Smith, founded the refuge in 1992. After a friend acquired a lion cub and realized …

U.S. Army Corps of Engineers, Little Rock District

Although technically a part of the U.S. Army, the U.S. Army Corps of Engineers (USACE) has played a vital role in the development of civilian transportation infrastructure and water resources since Congress passed the first river and harbors bill in 1824 and charged the corps with maintaining navigational channels. Work on the Ohio, Missouri, and Mississippi rivers received first priority, but as settlers moved farther west, attention soon focused on other navigable streams. Until 1916, Congress authorized only navigational improvements on rivers. Flood control only entered the corps’ mandate indirectly, as levees were considered navigational aids. However, as agricultural and transportation needs grew and the national economic importance of the lower Mississippi River Valley became evident, politicians found it easier …

University of Arkansas Rice Research and Extension Center

The University of Arkansas Rice Research and Extension Center (RREC), one of five research and extension centers in the University of Arkansas System’s statewide Division of Agriculture, is one of the best known and oldest rice research centers in the world. Arkansas produces almost half the rice grown in the United States, and the center has played a vital role in the success of the Arkansas rice industry. RREC is located nine miles east of Stuttgart (Arkansas County) on Highway 130. Originally called the Rice Branch Station, it was authorized by the Arkansas General Assembly in 1923, and work commenced on it in December 1926. The University of Arkansas (UA) in Fayetteville (Washington County) made an earlier attempt at establishing a …

Venomous Snakes

Arkansas hosts about forty-five species and subspecies of snakes, and six (thirteen percent) are species that use venom to obtain food and to defend themselves. There are two families of venomous snakes in the state: Elapidae (a single elapid species, the Texas coral snake) and Viperidae (five species of pitvipers). All of Arkansas’s venomous snakes inject venom through fangs via muscular contraction of paired venom glands. Texas Coral Snake The Texas coral snake, Micrurus tener tener (formerly Micrurus fulvius tenere) is a tricolored, medium-sized (maximum length = 122 centimeters), secretive elapid snake that primarily occurs in the southern and southwestern part of the state. Verified records are available for only five counties of the state in the Gulf Coastal Plain, …

Vines

In 2016, a total of 436 kinds of woody plants were known to occur in the wild in Arkansas, comprising 419 species plus another seventeen varieties and subspecies. Of these, 185 can be considered trees, 189 are best described as shrubs, and sixty-two are woody vines. In some cases, it is difficult to draw a hard line between these categories, and various reference works differ in their criteria for each. For the purposes of this entry, however, each category is defined as follows: Trees are defined as perennial, often single- or relatively few–stemmed woody plants typically greater than five meters (sixteen feet) in height at maturity. Shrubs are defined as perennial, often multi-stemmed woody or semi-woody plants usually less than …

Weather in the Civil War

Drought, flooding, bone-chilling winters, and intense summer heat all had an impact on the civilian and military populations of Arkansas during the Civil War, affecting military campaigns, access to food and supplies, and health conditions throughout the state. The Civil War was fought just after the end of a meteorological period that climate historians often call the Little Ice Age. This era, lasting roughly from 1300 to 1850, featured frequent climatic shifts, with bitterly cold winters switching to periods of heavy spring flooding, often followed by mild winters and subsequent droughts. While the trend toward cooling that characterized the Little Ice Age had moved toward warming by the 1860s, Civil War Arkansas would be plagued by temperature fluctuations that could …

Webspinners

aka: Footspinners
aka: Embiids
Webspinners or footspinners belong to the Phylum Arthropoda, Class Insecta, Subclass Pterygota, and Order Embioptera. They are a small group of mostly tropical and subtropical insects. More than 400 described species in eleven (eight extant) families are known, but it has been estimated that there might be around 2,000 extant species. Only three families (nine species) are present in North America: Anisembiidae (two species), Oligotomidae (three species), and Teratembiidae (four species). All of these occur in the southern United States, and most have fairly restricted ranges. At least two species occur in Arkansas, although very little is known about the embiopterans of the state. Embiopterans are found on every continent except Antarctica, with the highest density and diversity of species …

Western Mosquitofish

aka: Gambusia
The western mosquitofish (Gambusia affinis) belongs to the order Cyprinodontiformes and family Poeciliidae. The name “mosquitofish” is appropriate for this fish because its diet sometimes consists of large numbers of mosquito larvae. The family contains about twenty-one genera and 160 species. There are eight other freshwater species of Gambusia similar in appearance in North America north of Mexico, including the eastern mosquitofish (G. holbrooki), Amistad gambusia (G. amistadensis), Big Bend gambusia (G. gaigei), largespring gambusia (G. geiseri), San Marcos gambusia (G. georgei), Clear Creek gambusia (G. heterochir), Pecos gambusia (G. nobilis), and blotched gambusia (G. senilis). Many of these Gambusia spp. are endemic and afforded protection, as populations are either listed as threatened or endangered. The similar western mosquitofish ranges …

White Nose Syndrome

White nose syndrome (WNS) is an emerging disease caused by an exotic fungus of the Phylum Ascomycota, Class Dothideomycetes, and Family Pseudeurotiaceae. This fungus is native to Europe and perhaps portions of Asia and is specifically termed Pseudogymnoascus destructans (Pd). Pd was unknown to science and undescribed until it was identified in 2008. Initially named Geomyces destructans, it was reclassified as P. destructans in 2013. The fungus was first found in Asia and Europe, where scientists believe it had existed for some time, as host bats do not appear to get as ill from the disease it causes. The strain of Pd that made it to North America is thought to have originated from some locality in Europe. There is …

Wildflowers

The varied ecosystems in Arkansas enable a large variety of wildflowers to grow within the state. From the river deltas to the mountaintops, Arkansas boasts an abundant array of over 600 native wildflowers. The majority of wildflowers in Arkansas are along rural roads and secluded areas. Due to the growing population and changes in the environment, the areas in which wildflowers grow are in constant fluctuation. Although highways and the development of land have eliminated a majority of the state’s native wildflowers, programs are under way to preserve these flowers and bring them back to the roadways. Common Wildflowers The most common wildflowers on Arkansas highways today are as follows: An in-depth list with descriptions of Arkansas wildflowers was written …

Williams, Virginia Anne Rice

Biochemist Virginia Anne Rice Williams helped develop more nutritious grains through her pioneering studies of rice, a major Arkansas crop. She conducted important research on the B-vitamin content of rice, on ways to keep rice from turning rancid in storage, and on the vitamin fortification of rice. Virginia Rice was born in North Little Rock (Pulaski County) to Roderic J. Rice, a banker, and Mattie Thurman. Her high school teachers urged her to pursue music as a career, as she was a gifted musician. Fearing that she would not succeed as a concert musician, however, she opted for science, a field in which she also excelled. In 1940, Rice graduated from Hendrix College in Conway (Faulkner County) with a BA …

Willow Flycatchers

aka: Empidonax traillii
The willow flycatcher (Empidonax traillii) is the only bird species that has been discovered in the geographic area that is now the state of Arkansas. The noted naturalist and painter John James Audubon found the bird in 1822 while he was traveling near the community of Arkansas Post (Arkansas County), in what was then Arkansas Territory. When Audubon described the species in print for science in 1828, he named it Traill’s flycatcher for his friend Dr. Thomas Traill of Edinburgh, Scotland. Ornithologists have since determined that “Traill’s flycatcher” is really two different species, willow and alder flycatchers, which have almost identical appearances but distinctive vocalizations. The form Audubon discovered is of the species that was renamed willow flycatcher in 1973. …