Birthdays are good
Katelynn Wilton
Issue date: 10/26/09 Section: News
Last Friday, Professor Sherratt of Carleton University, presented on "The Evolution of Ageing" (yes, that is aging, spelled correctly, he claimed, from the other side of the river.) His talk, held at 4:00 p.m. in Science Center 213 presented research into the cause of aging. The work was done in collaboration with Dr. Rob Laird, who now works at Lethbridge University.
Dr. Sherratt began with a description of aging. Not only is it the physiological breakdown of the body with age, but it also entails the increased chance of mortality with increased age, along with a decreased fitness for reproduction. He explained to the audience that the chance of each person in the room dying approximately doubles every eight years, despite the age.
Dr. Sherratt then discussed aging as seen in other species. He explained that other animals also age. In particular, he showed trends in the damselfly and antler fly indicate senescence, which is normally considered a sign of age at the cell level. He also discussed how data can even be collected to show that the tyrannosaur showed signs of aging. In addition, bacteria also showed decreased ability to reproduce as they age.
However, although it seems like a grim topic, there is an upside. Dr. Sherratt described the "mortality plateaus" which show that although aging gets bad, and an individual's chance of death becomes high, but once it reaches a certain point, it does not get any worse. Humans display this pattern, particularly in incidences of cancer.
The question then became "why do we age?" Dr. Sherratt shared several modern theories on this question with the Clarkson audience. The first was named the "shit happens" theory. This theory indicates that various wear and tear occurs on the body, and eventually it wears out. Aging is just a sign of this damage to the body. However, Dr. Sherratt showed that it was not that simple. If that were true, then what would explain the different aging rates among and within species? Also, there is a heritable basis for variation, and long life can be selected for in some organisms. In addition, as his twins highlighted, many twin studies have corroborated this.
Dr. Sherratt began with a description of aging. Not only is it the physiological breakdown of the body with age, but it also entails the increased chance of mortality with increased age, along with a decreased fitness for reproduction. He explained to the audience that the chance of each person in the room dying approximately doubles every eight years, despite the age.
Dr. Sherratt then discussed aging as seen in other species. He explained that other animals also age. In particular, he showed trends in the damselfly and antler fly indicate senescence, which is normally considered a sign of age at the cell level. He also discussed how data can even be collected to show that the tyrannosaur showed signs of aging. In addition, bacteria also showed decreased ability to reproduce as they age.
However, although it seems like a grim topic, there is an upside. Dr. Sherratt described the "mortality plateaus" which show that although aging gets bad, and an individual's chance of death becomes high, but once it reaches a certain point, it does not get any worse. Humans display this pattern, particularly in incidences of cancer.
The question then became "why do we age?" Dr. Sherratt shared several modern theories on this question with the Clarkson audience. The first was named the "shit happens" theory. This theory indicates that various wear and tear occurs on the body, and eventually it wears out. Aging is just a sign of this damage to the body. However, Dr. Sherratt showed that it was not that simple. If that were true, then what would explain the different aging rates among and within species? Also, there is a heritable basis for variation, and long life can be selected for in some organisms. In addition, as his twins highlighted, many twin studies have corroborated this.
Be the first to comment on this story