Glossary M
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MAASTRICHTIAN AGE
The Maastrichtian age was the last part of the Cretaceous Period. It lasted
from about 71 to 65 million years ago, at the very end of the Mesozoic
Era. Many dinosuars existed during this age, but it ended with a major
mass extinction (the K-T extinction).
MACHAIRODUS
Machairodus (meaning: "knife tooth") was a common saber-toothed
cat that lived from about 15 million years ago until about 2 million years
ago. Species of this scimitar cat have been found in Africa, Europe, Asia,
and North America. This lion-sized meat-eating mammal had slender limbs
and a short tail; the upper jaw canine teeth were large. Machairodus was
named by Kaup in 1833. Classification: Family Felidae, Subfamily Machairodontinae,
Genus Machairodus, many species.
MACHAEROPROSOPUS
(pronounced ma-KEER-oh-pro-SOH-pus) Machaeroprosopus (meaning: "knife
face") was a phytosaur (not a dinosaur). This marine reptile had
a thin, knife-like crest of its skull (hence its name). This crocodile-like
animal had four short legs, a long tail, armored skin, sharp teeth in
elongated jaws, and nostrils near the eyes. It lived during the late Triassic
period. Fossils have been found in North America. Machaeroprosopus was
named by Mehl in 1916; the type species is Machaeroprosopus validus (but
the orginial speciemen has been lost).
MACROPLATA
Macroplata was a plesiosaur 15 feet (4.5 m) long with long, toothed jaws
and a long neck. From England during the early Jurassic Period. It was
not a dinosaur, but another type of extinct reptile.
MACRAUCHENIA
Macrauchenia was an early hoofed mammal with a long neck; it may have
had a long trunk. Macrauchenia was 10 feet ( 3 m) long; it had long legs,
three-toed, rhino-like feet, and nostrils located between the eyes. This
quadruped was an herbivore (a plant-eater). Macrauchenia lived during
the Pleistocene. Fossils have been found in Argentina, South America.
Classification: Class Mammalia (mammals), Order Litopterna (horse-like
and camel-like mammals), Family Macraucheniidae.
MAGNETIC FIELD
The Earth's magnetic field is aligned with the north and south poles,
and has reversed many times during geologic history. A fossil's magnetic
orientation can give clues to its date.
MAGYAROSAURUS
Magyarosaurus was a dwarf titanosaurid sauropod, a long-necked, long-tailed,
plant-eating dinosaur. It was 5 to 6 m long. Fossils have been found in
Hungary and Romania. Magyarosaurus lived during the late Cretaceous Period.
Magyarosaurus was named by the paleontologist von Huene in 1932; the type
species is M. dacus (Nopcsa, 1915 - originally called Titanosaurus).
Maiasaura
(pronounced MY-yah-SAWR-ah) Maiasaura (meaning: "good mother lizard")
was a duck-billed dinosaur (a hadrosaur) that cared for its young. This
plant-eater lived in herds during the late Cretaceous period, about 77
to 73 million years ago. Fossils of adults, juveniles, hatchlings, eggs,
and nests have been found in Montana, USA. Maiasaura was named by paleontologists
Jack Horner and R. Makela in 1979. The first dinosaur in space was Maiasaura
peeblesaurum (the type species). A piece of bone from a baby Maiasaura
and a Maiasaura eggshell were taken into space by astronaut Loren Acton
on an 8-day NASA mission (Spacelab 2) in 1985. The historic Maiasaura
fossils now reside at the Museum of the Rockies in Bozeman, Montana, USA.
MAJUNGASAURUS
(pronounced mah-JOONG-ah-SAWR-us) Majungasaurus (meaning: "Majunga
[Madagascar] lizard") was a large, meat-eating dinosaur from the
late Cretaceous Period, about 83-73 million years ago. Only a few fossils
(some teeth and tail vertebrae) of this theropod have been found on the
island of Madagascar. The type species is M. crenatissimus. Majungasaurus
was named by Lavocat in 1955. This is a dubious genus; it may be the same
as Majungatholus.
MAJUNGATHOLIS
(pronounced mah-JOONG-ah-THOL-us) Majungatholus (meaning: "Majunga
(Madagascar) dome" ) was a large, meat-eating dinosaur up to 30 feet
(9 m) long with a small horn above its eyes. The skull was nearly 2.5
feet (60 cm) long. It was a theropod but its classification is not certain;
it's possibly an abelisaurid. It was at the top of its local food chain
70 to 65 million years ago, during the late Cretaceous Period. Its fossil
was found on the island of Madagascar, off the east coast of Africa. It
is known from an incomplete adult specimen (skull and tail vertebrae)
and an incomplete juvenile (partial skull, partial spine). It was named
by Piveteau in 1926. Further work on Majungatholus was done by Sues and
Taquet in 1979. The type species is M. atopus. It used to be thought to
a pachycephalosaurid.
MALAWISAURUS
(pronounced mah-LAA-we-SAWR-us) Malawisaurus (meaning: "Malawi lizard")
was a huge, plant-eating dinosaur that lived during the early Cretaceous
period (roughly 140 million to 100 million years ago). This moderately-sized
titanosaurid sauropod was about 35 feet (10.5 m) long. It had a long neck,
a long tail, bulky body, and a small head (it was closely related to Janenschia).
It may have had some armored plates on its back. An incomplete fossils
was found in the Zambesi Valley, Malawi, Africa (Malawisaurus is the oldest-known
titanosaur from Africa). Malawisaurus was named by paleontologists Louis
L. Jacobs, Winkler, Downs, and Elizaneth M. Gomani in 1993. The type species
is M. dixeyi, (Haughton, 1928), and was originally called Gigantosaurus
dixeyi.
MALEEV, E. A.
Evgenii Aleksandrovich Maleev (1915-1966) was a Russian paleontologist
who named the dinosaur genera Talirurus (1952), Tarbosaurus (1955), and
Therizinosaurus (1954); he also named the family Therizinosauridae. The
dinosaurs Maleevosaurus (Pickering, 1984) and Maleevus (Tumanova, 1987)
were named by to honor Maleev.
MALEEVOSAURUS
(pronounded mahl-YAY-ev-oh-SAWR-us) Maleevosaurus (meaning: "Maleev's
lizard" named to honor the Russian paleontologist E. A. Maleev) was
a large meat-eating dinosaur, a tyrannosaurid that lived during the late
Cretaceous period. Maleevosaurus was found in Mongolia and named by Pickering
in 1984. The type species is M. novojilovi. Maleevosaurus may be the the
same as Tyrannosaurus bataar.
MALEEVUS
(pronounded mahl-YAY-ev--us) Maleevus (meaning: "Maleev's one"
named to honor the Russian paleontologist E. A. Maleev) was a large plant-eating
dinosaur, an ankylosaurid ankylosaur that lived during the late Cretaceous
period, about 99 to 90 million years ago. Maleevus (only a partial skull)
was found in Mongolia and named by Tumanova in 1987. The type species
is M. disparoserratus (originally called Syrmosaurus, and named by Maleev,
in 1952).
MALM EPOCH
The Malm epoch was the late (or upper) part of the Jurassic Period, about
159 to 144 million years
MAMENCHISAURUS
(pronounced mah-MEHN-chee-SAWR-us) Mamenchisaurus (meaning: "Mamenchi
(China) lizard" ) was a long-necked, long-tailed, quadrupedal, plant-eating
sauropod from the late Jurassic Period, about 156 million to 145 million
years ago. It was about 70 feet (21 m) long. Mamenchisaurus had the longest
neck of any known dinosaur, about 46 feet (14 m). It had 19 vertebrae
in its neck, more than any other known dinosaur. Mamenchisaurus was named
by Chung Chien Young in 1954. Fossils have been found in China. Mamenchisaurus
may be closely related to Diplodocus or Camarasaurus. The type species
is M. constructus.
Mammal
A mammal is a vertebrate which can regulate its body temperature, has
hair on its body, and mostly bears live young. It provide these with milk
from mammary glands.
MAMMOTH
Mammoths (genus name Mammuthus) are extinct herbivore mammals that had
long, dense hair and underfur, long tusks, a long proboscis (nose), large
ears. They lived throughout the world. They lived from about 2 million
years ago to 9,000 years ago, millions of years after the dinosaurs went
extinct. They are closely related to modern-day Indian elephants. Some
tusks were straight, some were curved; the longest were up to 13 feet
(4 m) long. The tusks were used in mating rituals, for protection, and
for digging in the snow for food. Much of our knowledge of mammoths is
from cave drawings and from mummified mammoths found in Siberian ice.
MANDASUCHUS
(pronounced MAN-dah-SOOK-us) Mandasuchus (meaning: "Manda crocodile"
the Manda Formation, Tanzania, is where the fossil was found) was a rauisuchian
(large-skulled archosaurs that may have been ancestors of dinosaurs) It
was not a dinosaur. It lived during the middle Triassic Period, roughly
220 million years ago. Fossils have been found in Tanzania, in east Africa.
This fast-runner was a quadruped about 8 feet (2.5 m) long; the rear legs
were slightly longer than the front legs. It may have been the fastest
reptile of its time. This meat-eater had a long tail, strong back (with
24 vertebrae between the head and hips), large, powerful jaws and sharp
teeth. Mandasuchus was named by Charig in 1976.
MANDIBLE
(pronounced MAN-dah-bul) The mandible is the lower jaw.
MANDIBLE
The Manicouagan impact structure is the remnants of an impact that occurred
about 200 million years ago. It is a ring of shattered rock (70 km across)
thats surrounds an area of rock that was melted by the tremendous impact
(and then solidified). The Manicouagan impact structure is located in
northern Quebec, Canada. This impact resulted from a 10 km diameter asteroid
and may have been responsible for the mass extinction that occurred at
the end of the Triassic Period.
MANIRAPTORS
Maniraptors are a group of bird-like animals, including Dromaeosaurs,
Oviraptors, Troodontids, Therizinosaurs, and Aves (birds). Maniraptors
are closer to birds than to Ornithomimus. Manirators have birds as a more
recent ancestor than Ornithomimus.
MANTELL, GIDEON
Gideon A. Mantell (1790-1852) was a British fossil hunter, one of the
first in the world. He named Hylaeosaurus (1833), Iguanodon (1825), and
Pelorosaurus (1850). Mary Ann Mantell, his wife, is commonly thought to
have found the first Iguanodon tooth in 1822; there is no substantiation
to this story, however.
MANUS
Manus is the scientific term for the hand (or forefoot) of a vertebrate
animal.