Metatheria is a group in the class Mammalia which contains the marsupials and the sparassodonts.
First proposed by Thomas Henry Huxley in 1880, it is nearly synonymous with the earlier taxon Marsupialia, but it also contains the nearest fossil relatives of marsupial mammals. They differ from all other mammals in their dental formula, which includes about five upper and four lower incisors, a canine, three premolars, and four molars.
The earliest known representative, "Sinodelphys", is from the Lower Cretaceous of China.
The closest relatives of the metatheres are the Eutheria (also erected by Huxley in 1880). Both are conventionally united as infraclasses within the subclass Theria, which contains all living mammals except monotremes.
During development, metatherians produce a yolk sac placenta and give birth to 'larval-like' offspring.
These offspring have underdeveloped rear limbs, and after birth they migrate to the marsupium where they attach to a nipple. The mouth of newly born metatherians forms an "O" shape into which the mother's nipple fits. Then it swells to secure the offspring into place.
The Greek words "meta-" and "theria" roughly means the ""other beasts"", in contrast with "Eutheria" (""true beasts"").
Metatherians first appeared in the Cretaceous period. Some stem group metatherians persisted well into the Neogene period before becoming extinct. Crown group marsupials, the one branch of Metatheria that survives today, diversified close to the time of extinction at the end of the Cretaceous.
Spermatic cord
The spermatic cord (also known as Van Deferens or Sperm Duct) is a cord-like structure in the male reproductive system that runs from the abdomen down to each testicle. It carries sperms from the epididymis to the urethra.
Mixed martial arts
Mixed martial arts (or MMA) is a hybrid martial arts form. It includes any mixture of combat disciplines or any blend of two or more styles of martial arts like boxing and kick boxing which are its integral fighting styles. MMA can also mean the sport of mixed martial arts fighting. Bellator, PFL, Rizin, ONE Championship, and UFC are companies that promote MMA sport fighting.
The people who organize a MMA fight can decide the rules for that fight.
There is no one group of people who decides the rules for all MMA fights,in the world. Some states regulate all professional fights including MMA fights and set some rules.
MMA fights once had few rules, but now have many rules to protect the fighters. Boxing (and other fighting sports) also have many rules, different from those in MMA.
Fighters can use any martial art, or combination of arts, they like in the fight. In these fights, fighters can fight standing with punches, kicks and other strikes, in a clinch where fighters are grabbing each other while standing, or on the ground.
An example of an illegal strike is the 12-6 elbow strike. It is illegal under the Unified Rules of Mixed Martial Arts, where it is called "striking downwards using the point of the elbow". The ban was made for medical and safety reasons, due to it being likely there would be serious injuries to opponents if they are used.
Each fighter will try to defeat the other either by submission, or knock out. Each fight can last only for a period of time, after the time ends, judges decide who is the winner. The referee in the fight will make sure no one gets hurt too badly and that rules are followed.
The pankration was an old style of unarmed combat. The ancient Greeks introduced this sport into the Olympic Games in the 648 BC. Some public fights took place at the end of the 19th century. They represented different styles of fighting, including jujutsu, wrestling, Greco-Roman wrestling and others in competitions and challenges across Europe. After World War I, wrestling was born again in two main flows. The first flow was real competition; the second flow began to depend more on the choreography and on the grand public shows that resulted in professional wrestling.
Modern mixed martial arts (MMA) has its roots in two kinds of competition: the Vale Tudo (Brazil) and Japanese Shootfighting.
Vale Tudo began circa 1930, when Carlson Gracie invited every competitor to compete in a fight. That was the so-called "Gracie's Challenge". Later, Hélio Gracie and the Gracie family continued this. Vale Tudo translates to "Anything Goes", as it had almost no rules.
In Japan, about 1970, Antonio Inoki organized a series of mixed martial arts fights. They were the forces that produced the Shootwrestling, and they later caused the developing of the first organization of mixed martial arts, known as Shooto. Mixed martial arts obtained great popularity in the United States in 1993, when Rorion Gracie helped create the first UFC event, one of the earliest MMA events in the USA . In 1997, in Japan, the interest for this sport resulted in the creation of the greater organization of mixed martial arts - Pride Fighting Championship.
The Gracie family caused the tournaments, as the UFC, to be well known. It should be noticed that the UFC is the most famous tournament, but the persons who practises Brazilian jiujitsu normally do not use blows. Undoubtedly, the Gracie family played an important role in the creation of open competitions of Vale Tudo and in causing them to be well known through the television. Nevertheless, before anyone created the UFC or Shooto, where the persons who represent every method of self-defense can fight, there had already existed such mixed martial arts.
About the year 1990, three styles were famous for their effectiveness in the competitions of the mixed martial arts: the wrestling, the Brazilian jiu-jitsu, and the shootwrestling. This can be because of their attention given to the combat by means of holds. Before the year 1990, the promoters organized a lacking amount of the competitions of the mixed martial arts, and some martial arts base on blows. Therefore, probably, most instructors of these arts had given too little attention to the holds.
Urarina
Urarina are Indigenous Peoples who live in the Peruvian Amazon Rainforest
Sergipe
Sergipe is the smallest state in Brazil. Aracaju is the capital and largest city. Sergipe borders two other states, Bahia and Alagoas.
Sergipe's land is mostly caatinga. A strip of rainforest runs down the Atlantic coast. There are also swamps near the coast.
Sergipe's main crop is sugarcane. Cassava is also grown. There is a small petoleum industry.
The first people to live in Sergipe were from the Tupi Tribe. The name "Sergipe" is the Tupi word for "crab".
The Portugal took over the area, and made a settlement at São Cristóvão. Later, French pirates invaded Sergipe, but they left soon after.
Now, Sergipe is part of free Brazil.
Soviet–Afghan War
The Soviet war in Afghanistan was a war initially fought between the forces of the Afghanistan government and Afghan assistance fighters, supporter from abroad. Without proper equipment and training, the Afghanistan government was unable to resist the opposition, called the Mujahideen, eventually seeking the aid of the Soviet Union. The entry of the Soviet Union into the country caused an immediate increase in the presence of foreign involvement. Massive military campaigns against the Mujahideen, who blended in with the local population, caused extensive destruction of local infrastructure and death, causing the local population to side with the Mujahideen. This change, among the local population, caused a loss of support for the Soviet military presence, creating nationwide resistance, and eventually a conflict. The war began in December 1979, and lasted until February 1989. About 15,000 Soviet soldiers were killed, and about 35,000 were wounded. About two million Afghan civilians were killed. The anti-government forces had support from many countries, mainly the United States and Pakistan.