Portal:Science

The Marwari, also known as the Malani is a rare breed of horse from the Marwar region of Rajasthan, in north-west India. It is closely related to the Kathiawari breed of the Kathiawar peninsula of Gujarat, with which it shares the distinctive inward-curving ears. Marwari horses are found in all equine colours, including piebald and skewbald. It is a hardy riding horse and may exhibit a natural ambling gait. (Full article...)

The history of timekeeping devices dates back to when ancient civilizations first observed astronomical bodies as they moved across the sky. Devices and methods for keeping time have gradually improved through a series of new inventions, starting with measuring time by continuous processes, such as the flow of liquid in water clocks, to mechanical clocks, and eventually repetitive, oscillatory processes, such as the swing of pendulums. Oscillating timekeepers are used in modern timepieces. Sundials and water clocks were first used in ancient Egypt c. 1200 BC and later by the Babylonians, the Greeks and the Chinese. Incense clocks were being used in China by the 6th century. In the medieval period, Islamic water clocks were unrivalled in their sophistication until the mid-14th century. The hourglass, invented in Europe, was one of the few reliable methods of measuring time at sea. (Full article...)

Velociraptor (/vəˌlɒsɪˈræptər, vəˈlɒsɪræptər/; lit. 'swift thief') is a genus of small dromaeosaurid dinosaurs that lived in Asia during the Late Cretaceous epoch, about 75 million to 71 million years ago (Mya). Two species are currently recognized, although others have been assigned in the past. The type species is V. mongoliensis, named and described in 1924. Fossils of this species have been discovered in the Djadochta Formation, Mongolia. A second species, V. osmolskae, was named in 2008 for skull material from the Bayan Mandahu Formation, China. A possible record is known from the Nemegt Formation. (Full article...)

Maya stelae (singular stela) are monuments that were fashioned by the Maya civilization of ancient Mesoamerica. They consist of tall, sculpted stone shafts and are often associated with low circular stones referred to as altars, although their actual function is uncertain. Many stelae were sculpted in low relief, although plain monuments are found throughout the Maya region. The sculpting of these monuments spread throughout the Maya area during the Classic Period (c. 250 – c. 900 AD), and these pairings of sculpted stelae and circular altars are considered a hallmark of Classic Maya civilization. The earliest dated stela to have been found in situ in the Maya lowlands was recovered from the great city of Tikal in Guatemala. During the Classic Period almost every Maya kingdom in the southern lowlands raised stelae in its ceremonial centre. (Full article...)

Omayra Sánchez Garzón (August 28, 1972 – November 16, 1985) was a Colombian girl trapped and killed by a landslide when she was 13 years old. (Full article...)

Dinosaurs are a diverse group of warmblooded reptiles of the clade Dinosauria. They existed through most of the Mesozoic era, first appearing early in the Triassic period. They became the dominant terrestrial vertebrates after the Triassic–Jurassic extinction event 201.3 mya and their dominance continued throughout the Jurassic and Cretaceous periods. The fossil record shows that birds are feathered dinosaurs, having evolved from earlier theropods during the Late Jurassic epoch, and are the only dinosaur lineage known to have survived the Cretaceous–Paleogene extinction event approximately 66 mya. Dinosaurs can therefore be divided into avian dinosaurs—birds—and the extinct non-avian dinosaurs, which are all dinosaurs other than birds. (Full article...)

The European rabbit (Oryctolagus cuniculus) or coney is a species of rabbit native to the Iberian Peninsula and southwestern France. It has been introduced to hundreds of locations around the world. Wild and domesticated European rabbits around the world can vary widely in size, shape, and colour. The average adult European rabbit is smaller than the European hare, though size and weight vary with habitat and diet. (Full article...)

The king brown snake (Pseudechis australis) is a species of highly venomous snake of the family Elapidae, native to northern, western, and Central Australia. The king brown snake is the largest terrestrial venomous snake in Australia. Despite its common name, it is a member of the genus Pseudechis (black snakes) and only distantly related to true brown snakes. Its alternative common name is the mulga snake, although it lives in many habitats apart from mulga. First described by English zoologist John Edward Gray in 1842, it is a robust snake up to 3.3 m (11 ft) long. It is variable in appearance, with individuals from northern Australia having tan upper parts, while those from southern Australia are dark brown to blackish. Sometimes, it is seen in a reddish-green texture. The dorsal scales are two-toned, sometimes giving the snake a patterned appearance. Its underside is cream or white, often with orange splotches. The species is oviparous. The snake is considered to be a least-concern species according to the International Union for Conservation of Nature, though may have declined with the spread of the cane toad. (Full article...)

Thyrotoxic periodic paralysis (TPP) is a rare condition featuring attacks of muscle weakness in the presence of hyperthyroidism (overactivity of the thyroid gland). Hypokalemia (a decreased potassium level in the blood) is usually present during attacks. The condition may be life-threatening if weakness of the breathing muscles leads to respiratory failure, or if the low potassium levels lead to abnormal heart rhythms. If untreated, it is typically recurrent in nature. (Full article...)

Hydnellum peckii is a fungus in the genus Hydnellum of the family Bankeraceae. The unusual appearance of the young fruit bodies has earned the species several descriptive common names, including strawberries and cream, the bleeding Hydnellum, the bleeding tooth fungus, the red-juice tooth, and the Devil's tooth. (Full article...)

RNA interference (RNAi) is a biological process in which RNA molecules are involved in sequence-specific suppression of gene expression by double-stranded RNA, through translational or transcriptional repression. Historically, RNAi was known by other names, including co-suppression, post-transcriptional gene silencing (PTGS), and quelling. The detailed study of each of these seemingly different processes elucidated that the identity of these phenomena were all actually RNAi. Andrew Fire and Craig Mello shared the 2006 Nobel Prize in Physiology or Medicine for their work on RNAi in the nematode worm Caenorhabditis elegans, which they published in 1998. Since the discovery of RNAi and its regulatory potentials, it has become evident that RNAi has immense potential in suppression of desired genes. RNAi is now known as precise, efficient, stable and better than antisense therapy for gene suppression. Antisense RNA produced intracellularly by an expression vector may be developed and find utility as novel therapeutic agents. (Full article...)

The Caerleon pipe burial is a second-century Roman grave from a cemetery associated with the former legionary fortress and settlement, Isca Augusta, in what is now Caerleon, Wales, United Kingdom. The main site, including its large amphitheatre, was excavated in the early twentieth century, largely by the archaeologist Tessa Wheeler, but its surrounding cemeteries were mainly known only through casual discoveries. (Full article...)

The bobcat (Lynx rufus), also known as the wildcat, bay lynx, or red lynx, is one of the four extant species within the medium-sized wild cat genus Lynx. Native to North America, it ranges from southern Canada through most of the contiguous United States to Oaxaca in Mexico. It is listed as Least Concern on the IUCN Red List since 2002, due to its wide distribution and large population. Although it has been hunted extensively both for sport and fur, populations have proven stable, though declining in some areas. (Full article...)

Banksia sessilis, commonly known as parrot bush, is a species of shrub or tree in the plant genus Banksia of the family Proteaceae. It had been known as Dryandra sessilis until 2007, when the genus Dryandra was sunk into Banksia. The Noongar peoples know the plant as budjan or butyak. Widespread throughout southwest Western Australia, it is found on sandy soils over laterite or limestone, often as an understorey plant in open forest, woodland or shrubland. Encountered as a shrub or small tree up to 6 m (20 ft) in height, it has prickly dark green leaves and dome-shaped cream-yellow flowerheads. Flowering from winter through to late spring, it provides a key source of food—both the nectar and the insects it attracts—for honeyeaters in the cooler months, and species diversity is reduced in areas where there is little or no parrot bush occurring. Several species of honeyeater, some species of native bee, and the European honey bee seek out and consume the nectar, while the long-billed black cockatoo and Australian ringneck eat the seed. The life cycle of Banksia sessilis is adapted to regular bushfires. Killed by fire and regenerating by seed afterwards, each shrub generally produces many flowerheads and a massive amount of seed. It can recolonise disturbed areas, and may grow in thickets. (Full article...)

George Ward (30 November 1993 – 18 September 2022), better known by the stage name Cherry Valentine, was an English drag queen and mental health nurse who competed in the second series of the television show RuPaul's Drag Race UK. Raised in a Romanichal community, Ward has been credited as the first contestant on the Drag Race franchise to acknowledge his Romani heritage. In 2022, he addressed his background in the BBC documentary film Cherry Valentine: Gypsy Queen and Proud, and in an episode of the documentary series God Shave the Queens. Following Ward's suicide in 2022, a memorial concert and fundraiser was held at London's Clapham Grand. (Full article...)