Glossary BAK - BEC
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BACKGROUND EXTINCTIONS
Background extinctions are those extinctions that occur continually throughout
time. These extinctions are caused by small changes in climate or habitat,
depleted resources, competition, and other changes that require adaptation
and flexibility. Most extinctions (perhaps up to 95 per cent of all extinctions)
occur as background extinctions.
BACTERIA
Bacteria are one-celled, microscopic organisms that live all over the
world. They are important in the decay of organic material and in the
fixing of nitrogen.
BACTROSAURUS
(pronounced BACK-tra-SAWR-us) Bactrosaurus or Bactrasaurus (which means
'club-spined lizard') was a large, plant-eating, duck-billed dinosaur
(a lambeosaurid hadrosaurine), up to about 20 feet (6 m) long, weighing
roughly 1500 kg. Its femur (thigh bone was 80 cm long. About six fragmentary
Bactrosaurus fossils were found in Mongolia and China. It lived during
the late-Cretaceous Period, about 97-85 million years ago and was named
by C.W. Gilmore in 1933. The type species is B. johnsoni.
BACULITES
Baculites (which means "walking stick rock") was a genus of
ammonite that lived during the late Cretaceous Period. It was heteromorphic:
in its juvenile stages it had a coiled shell; as an adult, it was straight-shelled,
tube-like, and about 2 m long (but some later forms had a cork-screw shape).
Baculites was a wide-spread marine cephalopod mollusk that may have lived
in colonies on the sea floor. Baculites species are very widespread, so
they are used as an index fossil. Baculites was named by the French paleontologist
Alcide Dessalines d'Orbigny in 1850.
BADLANDS
Badlands are barren, severely eroded places on Earth where the soft rock
layers are sculpted into beautiful forms. These exposed rock layers are
often wonderful places in which to find fossils. They're called badlands
because the land is useless for farming and many other human purposes.
BAGACERATOPS
(pronounced BAG-uh-CER-uh-TOPS) Bagaceratops (meaning: "small horned
face") was a ceratopsian dinosaur about 3 feet (1 m) long. Bagaceratops
weighed rouhghly 65 pounds (30 kg). It was a quadrupedal plant-eater with
a short neck frill and a small horn on its snout. It lived in what is
now Mongolia, China during the late Cretaceous Period, about 70 million
years ago. It was described by Halszaka Osmólska in 1975. The type species
is B. rozhdestvenskyi.
BAGARAATAN
(pronounced BAG-ah-RAH-tahn) Bagaraatan (meaning: "small hunter"
) was a speedy, bipedal, meat-eating dinosaur (an early coelurosaur).
This theropod was about 11.5 feet (3.5 m) long and dates from the late
Cretaceous Period. An incomplete skeleton was found in Mongolia and was
named by paleontologist Osmolska in 1996. The type species is B. ostromi.
BAHARIASAURUS
(pronounced bah-hah-REE-ya-SAWR-us) Bahariasaurus (meaning: "oasis
lizard") was a theropod dinosaur (perhaps a carnosaur) about 20-40
feet (6-12 m) long, weighing about 4 tonnes. It was a bipedal meat-eater
from what is now Egypt. It lived during the Cretaceous Period, about 109
to 95 million years ago. It was named by Stromer in 1934. The type species
is B. ingens. The only known fossil was destroyed in World War II.
BAKKER, ROBERT
Robert Bakker (1945- ) is a US paleontologist and dinosaur artist who
revolutionized our view of dinosaurs in the late 1960's, drawing them
as active animals standing upright and not dragging their tails. He named:
Chassternbergia (1988), Denversaurus (1988), Drinker (1990, with others),
Edmarka (1992, with others), and Nanotyrannus (with others, 1988).
BALUCHITHERIUM
Baluchitherium (now called Indricotherium) is a large, extinct, hornless
rhinoceros. It was one of the largest land mammals. Adults were about
26 feet (8 m) long, 18 feet (5.5 m) tall, and weighed about 17 - 18 tons
(16 tonnes). The skull was 4.25 feet (1.3 m) long. This herbivore ate
leaves and twigs from the tops of trees. It had four teeth; two tusk-like
front teeth in the top jaw, pointing down and two on the bottom pointing
forwards. This extinct ungulate (hoofed mammal) had three toes on each
foot and lived from the Oligocene to the early Miocene in central Asia
(Pakistan, Mongolia and China). Classification: Order Perissodactyla (odd-toed
ungulates), Family Hyrachyidae (odd-toed ungulates between tapirs and
rhinos).
BAMBIRAPTOR OR BAMBI
(pronounced BAM-be-RAP-tor) Bambiraptor (also known as Bambi) was a juvenile
coelurosaur, an advanced theropod (meat-eating dinosaur). This small predator
was originally thought to be a juvenile Velociraptor or perhaps Saurornitholestes
langstoni. It was a small, fast, meat-eating dromaeosaurid dinosaur from
the late Cretaceous Period. Bambiraptor was about 3 feet (1 m) long and
may have weighed about 7 pounds (3 kg). It had a deadly, sickle-shaped
toe claw on the second toe of its foot. Bambiraptor was found in the upper
Two Medicine Formation, Montana, USA. The nearly complete, fossilized
skeleton was found in a dinosaur bonebed, near a Maiasaura skull. Bambiraptor
was named by Burnham, Derstler, Currie, Bakker, Zhou, and Ostrom, 2000.
The type species is Bambiraptor feinbergi.
BARAPASAURUS
(pronounced buh-RAH-pah-SAWR-us) Barapasaurus (meaning: "big-legged
lizard") was a sauropod (a long-necked, long-tailed, small-headed,
short-legged giant). It was an herbivore, a plant-eater that was about
60 feet (20 m) long, weighing roughly 48400 kg. The femur (thigh bone)
is 5.5 ft (1.70 m) long. Barapasaurus lived during the early Jurassic
Period, about 208 to 188 million years ago. 6 partial skeletons have been
found in Southern India's Godavari Valley, but no skulls or feet have
been found. It ay belong to the family vulcanodintidae, but this is unsure.
Barapasaurus was named by Jain, Kutty, Roy-Chowdhury and Chatterjee in
1975. The type species is B. tagorei.
BARBOUROFELIS
Barbourofelis (meaning: "Barbour's cat") was a carnivorous (meat-eating)
mammal, an early cat with long incisors - it was not a dinosaur. This
lion-sized cat was the last of the family Nimravidae (false-saber-tooth
cats) and lived during the late Miocene, about 15-7 million years ago.
Fossils have been found in North America, Turkey, and Spain. Classification:
Class Mammalia (mammals), Order Carnivora, Superfamily Feloidea (cats,
mongooses), Family Nimravidae (false-saber-tooth cats, early cats), Genus
Barbourofelis.
BAROSAURUS
(pronounced BAR-oh-SAWR-us) Barosaurus (meaning: "heavy lizard")
was a diplodocid sauropod (a long-necked, long-tailed, small-headed, short-legged
giant). It was an herbivore, a plant-eater. It was huge and slow-moving,
perhaps over 60 to 88 feet (20-27 m) long, weighing roughly 40000 kg.
Its femur (thigh bone) was 8.2 ft (2.52 m) long. Its primary defense against
predators was its size. Barosaurus lived during the late Jurassic Period,
about 156 to 145 million years ago. Its fossils have been found in western
North America and East Africa. Barosaurus was named by paleontologist
Othniel C. Marsh in 1890. The type species is B. lentus.
BARSBOLD, RINCHEN
Rinchen Barsbold is a Mongolian paleontologist. He named: Adasaurus (1983),
Ansermimus (1988), Conchoraptor (1986), the family Enigmosauridae (1983),
Enigmosaurus (with A. Perle, 1983), Gallimimus (with H. Osmólska and E.
Roniewicz, 1972), Garudimimus and the family Garudimimidae (1981), Harpymimus
and the family Harpymimidae (with A. Perle, 1984), Ingenia (1981), the
family Ingeniidae (1986), the family Oviraptoridae (1976), and the suborder
Segnosauria (with A. Perle, 1980). Barsboldia (Maryanska et Osmolska,
1981) was named to honor Rinchen Barsbold.
BARSBOLDIA
(pronounced bars-BOWL-dee-ah) Barsboldia (named for Rinchen Barsbold)
was a duck-billed dinosaur (a lambeosaurine hadrosaur) about 30 feet (10
m) long, weighing roughly 6500 kg. It was a quadrupedal plant-eater with
a hollow crest and tall spines on its back vertebrae (which may have formed
a fin on its back). It lived in what is now Mongolia during the late Cretaceous
Period, about 70 million years ago. The type species is B. sicinskii.
It was named by Maryanska and Osmolska in 1981. This is a doubtful genus
since it is so poorly known.
Baryonyx
A large 9 metre long theropod from the early Cretaceous period. With a
long crocodile-like head and relatively long arms with huge curved claws
on the thumbs, Baryonyx may have been primarily a fish-eater. It is known
from a relatively well-preserved skeleton found in a quarry in Surrey,
England by an amateur fossil hunter in 1983.
BASILOSAURUS
Basilosaurus was an Archaeoceti whale, a primitve, extinct whale from
the Eocene epoch, 50 million of years ago.
BASUTODON
(pronounced buh-SUE-TOE-don) Basutodon (meaning: "Basuto [former
name of Lesotho, South Africa] tooth") is a dubious genus of reptile
that may or may not be dinosaurian. Fossil teeth that date from the Triassic
period were found in South Africa. Basutodon was named by paleontologist
von Huene in 1932. The type species is B. ferox.
BAVARISAURUS
Bavarisaurus was a small, fast-moving, ancient lizard (it was not a dinosaur)
that lived during the Jurassic period. A partially digested, fossilized
skeleton of a Bavarisaurus was found inside a Compsognathus (a small,
meat-eating dinosaur) fossil in Bavaria, Germany.
BECKLESPINAX
Becklespinax (meaning: "Beckles' spine") was a theropod dinosaur
(a tetanurid) about 15 feet (5 m) long. It was a bipedal meat-eater with
spines along its back. It lived in what is now England during the early
Cretaceous Period, about 125 million years ago. It is only known from
three elongated vertebrae and teeth found by Samuel H. Beckles in the
1850's. It was named by paleontologist Olshevsky in 1991.