Skip to main content

Pinned Post

Battle of Iwo Jima Facts, Significance, Photos, & Map

 Battle of Iwo Jima Date 19 February – 26 March 1945 (1 month and 1 week) Location  Iwo Jima, Volcano Islands, Japan Result  American victory USAAF fighter aircraft able to escort B-29's on missions to Japan. Americans gain an emergency landing base for damaged aircraft returning from missions on Japan. Belligerents  United States  Japan Commanders and leaders U.S. Navy: Chester W. Nimitz Raymond A. Spruance Marc A. Mitscher William H. P. Blandy U.S. Marine Corps: Holland M. Smith Harry Schmidt Graves B. Erskine Clifton B. Cates Keller E. Rockey Tadamichi Kuribayashi † Takeichi Nishi † Sadasue Senda † Rinosuke Ichimaru † Units involved American: Ground units: V Amphibious Corps 3rd Marine Division 4th Marine Division 5th Marine Division 147th Infantry Regiment (separate) Aerial units: Seventh Air Force Naval units: 5th Fleet Joint Expeditionary Force (TF 51) Amphibious Support Force (TF 52) Attack Force (TF 53) Expeditionary Troops (TF 56) Fast Carrier Force (T...

Mammoth-Definition, Size, Height, Picture, & Facts

 Mammoth (extinct)



Range of  Mammoth


Scientific classification

Kingdom:

Animalia

Phylum:

Chordata

Class:

Mammalia

Order:

Proboscidea

Family:

Elephantidae

Genus:

†Mammuthus


mammoth, (genus Mammuthus), any member of an extinct group of elephants found as fossils in Pleistocene deposits over every continent except Australia and South America and in early Holocene deposits of North America. (The Pleistocene Epoch began 2.6 million years ago and ended 11,700 years ago. The Holocene Epoch began 11,700 years ago and continues through the present.)

The woolly, Northern, or Siberian mammoth (Mammuthus primigenius) is by far the best-known of all mammoths. The relative abundance and, at times, excellent preservation of this species’s carcasses found in the permanently frozen ground of Siberia has provided much information about mammoths’ structure and habits. Fossil mammoth ivory was previously so abundant that it was exported from Siberia to China and Europe from medieval times. Scientific evidence suggests that small populations of woolly mammoths may have survived in North America until between 10,500 and 7,600 years ago. An examination of a fossil tooth discovered in 2015 indicated that a tiny population of mammoths persisted on Wrangel Island, an Arctic island located off the coast of northern Russia, as late as 4,300 years ago before succumbing to extinction from the effects of inbreeding and the loss of genetic diversity. The oldest preserved mammoth DNA, which also has the distinction of being the oldest known animal DNA, dates to more than one million years ago and may belong to a direct ancestor of the woolly mammoth.

Lyuba, the most well-preserved woolly mammoth (Mammuthus primigenius) ever found, on display at the Field Museum, Chicago. It died in Siberia about 42,000 years ago and was about one month old.


Mammoths figured significantly in the art of primitive humans; cave dwellers in Europe realistically depicted herds of these animals. Mammoths were sometimes trapped in ice crevasses and covered over; they were frozen, and their bodies were remarkably well preserved. In fact, cases have been reported in which sled dogs actually were fed the meat from frozen mammoth carcasses that had begun to thaw out of the ice that had held them for almost 30,000 years.

A variety of distinct species are included in the genus Mammuthus. Most mammoths were about as large as modern elephants. The North American imperial mammoth (M. imperator) attained a shoulder height of 4 metres (14 feet). At the other extreme were certain dwarfed forms whose ancestors became isolated on various islands. Many mammoths had a woolly, yellowish brown undercoat about 2.5 cm (1 inch) thick beneath a coarser outer covering of dark brown hair up to 50 cm (20 inches) long. Under the extremely thick skin was a layer of insulating fat at times 8 cm (3 inches) thick. The skull in Mammuthus was high and domelike. The ears, small for an elephant, were probably adaptively advantageous for an animal living in a cold climate; the smaller amount of exposed surface area diminished heat losses. A mound of fat was present as a hump on the back. This structure is lacking in fossil remains, but evidence for its presence comes from cave paintings. The prominent tusks were directed downward and were very long; in older males they sometimes curved over each other. Mammoth dentition was made up of alternating plates of enamel and a denture that often became worn down by constant back-to-front chewing motions. Remains of arctic plants have been found in the digestive tracts of frozen mammoth carcasses. It is clear that the mammoth was hunted by early North American hunters.

Comments

Popular posts from this blog

Roman Legion

 Roman legion Roman Legionary  Map of Roman legions by 14 AD legion, a military organization, originally the largest permanent organization in the armies of ancient Rome. The term legion also denotes the military system by which imperial Rome conquered and ruled the ancient world. The expanding early Roman Republic found the Greek phalanx formation too unwieldy for fragmented fighting in the hills and valleys of central Italy. Accordingly, the Romans evolved a new tactical system based on small and supple infantry units called maniples. Each maniple numbered 120 men in 12 files and 10 ranks. Maniples drew up for battle in three lines, each line made up of 10 maniples and the whole arranged in a checkerboard pattern. Separating each unit was an interval equivalent to a maniple’s front of 18 m (60 feet), so that the maniples of the first line could fall back in defense into the intervals of the second line. Conversely, the second line could merge with the first to form a solid f...

Battle of Iwo Jima Facts, Significance, Photos, & Map

 Battle of Iwo Jima Date 19 February – 26 March 1945 (1 month and 1 week) Location  Iwo Jima, Volcano Islands, Japan Result  American victory USAAF fighter aircraft able to escort B-29's on missions to Japan. Americans gain an emergency landing base for damaged aircraft returning from missions on Japan. Belligerents  United States  Japan Commanders and leaders U.S. Navy: Chester W. Nimitz Raymond A. Spruance Marc A. Mitscher William H. P. Blandy U.S. Marine Corps: Holland M. Smith Harry Schmidt Graves B. Erskine Clifton B. Cates Keller E. Rockey Tadamichi Kuribayashi † Takeichi Nishi † Sadasue Senda † Rinosuke Ichimaru † Units involved American: Ground units: V Amphibious Corps 3rd Marine Division 4th Marine Division 5th Marine Division 147th Infantry Regiment (separate) Aerial units: Seventh Air Force Naval units: 5th Fleet Joint Expeditionary Force (TF 51) Amphibious Support Force (TF 52) Attack Force (TF 53) Expeditionary Troops (TF 56) Fast Carrier Force (T...

The battle of Hattin facts, location, leaders & history

 The Battle of Hattin  Date 3–4 July 1187 Location  Horns of Hattin, Principality of Galilee (modern-day Israel) 32°48′13″N 35°26′40″E Result  Decisive Ayyubid victory Belligerents Kingdom of Jerusalem County of Tripoli Principality of Antioch Knights Templar Knights Hospitaller Order of Saint Lazarus Order of Mountjoy Ayyubid Sultanate Commanders and leaders Guy of Lusignan Surrendered Raymond III of Tripoli Balian of Ibelin Gerard de Rideford Surrendered Garnier de Nablus Raynald of Châtillon Surrendered Executed Humphrey IV of Toron Aimery of Lusignan Reginald of Sidon Joscelin III of Edessa Saladin Muzaffar ad-Din Gökböri Al-Muzaffar Umar Al-Adil I Al-Afdal ibn Salah ad-Din Strength 18,000–20,000 men 1,200 knights 3,000 men-at-arms 500 turcopoles 15,000 infantry 20,000–40,000 men 12,000 regular cavalry Casualties and losses Crusaders Casualties Most of the army 200 captured knights executed Captured turcopoles executed Captured infantrymen enslaved Muslims casua...