This group has at times been classified with the sharks: the similarities are obvious, not only do the chondrosteans mostly lack bone, the structure of the jaw is more akin to that of sharks than other bony fish. Both lack scales (except the Polypteriforms). Additional shared features include spiracles and, in sturgeons, a heterocercal tail (the vertebrae extend into the larger lobe of the caudal fin). However the fossil record suggests that these fish have more in common with the Teleostei than their external appearance might suggest.
It is thought that the ancestors of the chondrosteans were bony fish but that this characteristic was lost in later evolutionary development, resulting in a lightening of the frame. Elderly chondrosteans show beginnings of ossification of the skeleton which suggests that this process is delayed rather than lost in these fish.
In the early Mesozoic, a number of fish families were beginning to develop adaptations which would make them lighter, faster and more efficient predators. Chondrosteans took a radical approach. Cartilage is lighter than bone, and they delayed the development of bone, so that it only developed in elderly fish. They lost the upper jaw bones completely. Other changes allowed them to shoot the jaw forwards to grab prey.
Why did Chondrosteans react with such total reorganization? Obviously selection pressure must have been very strong. However, in one way they were almost unique. Rarely amongst animals, they underwent polyploidy, several times. Instead of two sets of chromosomes (diploid), the Chondrosteans have 8 or 16 sets of chromosomes. Such a dramatic genetic change may have given the potential for a rapid, drastic reorganization of the body plan.
The Chondrostei are paraphyletic. The group does not contain all of its descendants. Therefore, sooner or later, it is going to be reorganised.
Don Meredith
"Dandy Don" Meredith (April 10, 1938 - December 6, 2010) was an American football player. He was born in Mount Vernon, Texas (about 100 miles east of Dallas. He died in Santa Fe, New Mexico from a brain hemorrhage. He was 72 years old. Meredith was a quarterback for the Dallas Cowboys from 1960-1968. In 1970 he became a television broadcaster when he joined the Monday Night Football crew.
Meredith studied at Southern Methodist University (SMU). He played quarterback for SMU for three years. He was selected as an All-America in 1958 and 1959. In 1960, he was drafted by the Chicago Bears in the third round. He was then traded to the Dallas Cowboys for future draft picks. In 1960, the Cowboys were a newly formed "expansion" team.
Meredith played quarterback for the Cowboys from 1960 to 1968. In 1965, he became the starting quarterback. In 1966, he led the Cowboys to their first winning season, with a record of ten wins, three losses, and one tie. He threw a career-high 2,805 yards and 24 touchdown passes. He was named NFL Player of the Year and selected to the Pro Bowl. He led the Cowboys to three division titles. He played in the 1966 and 1967 NFL Championship games.
"Dandy Don" announced his retirement in 1969, the same day that Roger Staubach was released from the Navy. Staubach then replaced Meredith as the quarterback. Meredith was 31 years old and in the prime of his career.
Meredith was inducted to Cowboys "Ring of Honor" in 1976. He and Don Perkins were the second and third players added to the ring.
Don Meredith was one of the first athletes to move into television broadcasting as a color commentator. He joined Keith Jackson and Howard Cosell at Monday Night Football (MNF) in 1970. In 1973, he left MNF to join NBC for three years. In 1977, he returned to MNF until his retirement in 1984. He also appeared in a number of TV shows and movies, including "Police Story" and commercials for Lipton Ice Tea.
Ron Talakoski
Ronald Paul Isaac Talakoski (June 1, 1962 – July 7, 2009) was a Canadian professional ice hockey right winger who played nine games in the National Hockey League with the New York Rangers between 1986 and 1988.
Talakoski spent four years at the University of Manitoba. In October, 1986 he signed as a free agent with the New York Rangers and played three games for the club that season. The rest of his rookie year was spent in the American Hockey League (AHL) and the International Hockey League (IHL). In 1987-88 he played a six games for the Rangers then scored 24 goals for the IHL's Colorado Rangers before retiring. Talakoski also served as a firefighter in Thunder Bay, Ontario for 18 years. Talakoski was found dead by Thunder Bay Fire and Rescue Services after a short search near Pier 3 in Thunder Bay, after having been reported missing from his residence. He is reported to have suffered from Shy-Drager syndrome.
Lifeboat
A lifeboat, also known as a liferaft, is a small, stiff or inflatable boat carried for emergencies in the event of a disaster on a ship. Lifeboats are required by law to be on larger ships.
When steamships became commonplace in the 19th century, so did lifeboats. At the beginning of the 20th century larger ships meant that more people could travel, but rules about lifeboats were often overlooked. After the RMS Titanic sank on April 15, 1912, people realized that bigger ships need more lifeboats. The Titanic's lifeboats were only capable of carrying 1,178 people although the Titanic had 3,330 people.
Because many lifeboats were needed on the decks of passenger ships this led to the use of most of the deck space being used for lifeboats which created the problem of narrow passageways. This was fixed by inflatable lifeboats being used.
Overpopulation
Overpopulation means that the population of a place is too high. Specifically, there are too many organisms of a certain species in a habitat, so the number of organisms living there is larger than the carrying capacity of the habitat. The habitat cannot support these numbers over time without hurting itself.
The term "overpopulation" is most often used to refer to the number of humans living on Earth.
The world's population has greatly increased in the last 50 years. The main reason is the reduction in death rate, especially for infants and children. The result is that many more people survive to the age when reproduction is possible.
Steve Jones, head of the biology department at University College London, has said,
Against this background, the reduction in fertility has had little effect, except perhaps in China. The use of the contraceptive pill has transformed the lives of women in rich countries, but has made little impact in poor ones.
The recent rapid increase in human population over the past two centuries has raised concerns that humans are beginning to overpopulate the Earth. The planet may not be able to sustain larger numbers of people. The population has been growing since the end of the Black Death, around the year 1400. At the beginning of the 19th century, it had reached roughly 1,000,000,000 (one billion). Rapid population growth occurred all over the world, especially after World War II. By 1960, the world population had reached 3 billion, and it doubled to 6 billion over the next four decades. As of 2011, the estimated annual growth rate was 1.10%, down from a peak of 2.2% in 1963, and the world population stood at roughly 6.9 billion. In 2014, it is over seven billion.
Current projections show a steady decline in the population growth rate, with the population expected to reach between 8 and 10.5 billion between the year 2040 and 2050.