A QUANTUM OF SCIENCE
This just in: women like looking at "attractive" babies more than men do. That's unlikely to make any headlines, but the reverse case is where the surprise comes in: if a baby is "unattractive" through some objective standard, women like looking at it *less* than men do.
Researchers at the Clinical Psychopathology Laboratory or McLean Hospital and Harvard Medical School in Boston report that the length of time that women vs. men spent looking at "normal" babies versus those affected by cleft palate, Down's Syndrome or other congenital birth defects were reversed: women spent longer looking at the "normal" babies than men did, but much less time looking at "unattractive" babies than men did. The authors of the study suggest that this might reflect an evolutionary bias on the part of women to spend less time and attention on the less viable of their offspring, correlating subjective lack of aesthetic appeal with decreased potential for viability.
For more information:
Gender Differences in the Motivational Processing of Babies Are Determined by Their Facial Attractiveness (Yamamoto et al.)
© A Quantum of Science / P. Smalley
Reproduction with attribution is appreciation
Showing posts with label evolution. Show all posts
Showing posts with label evolution. Show all posts
Thursday, July 9, 2009
Thursday, May 28, 2009
Quantum: Ancient immunity
A QUANTUM OF SCIENCE
New findings show adaptive immune system may not be new invention
Recently, scientists at Emory University in Atlanta reported that lampreys - a cartilaginous fish which evolved around 500 million years ago - is the oldest organism yet found to possess an adaptive immune system like that of humans. Previously, the adaptive immune system was believed to have originated in sharks, which evolved around 400 million years ago. This extra 100 million years is a big deal because the lamprey is a much earlier splinter from the vertebrate branch of the tree of life, and could mean that other even more ancient predecessors had already figured out how to "record" microbial invaders and repel them better in future infections.
Another interesting note: the age of cartilaginous fishes was known as the Silurian period, a time culminating in the so-called Law Event in which approximately 60% of aquatic species became extinct through a series of rapid climatic changes. Could the adaptive immune system have helped lampreys and sharks survive?
For more information:
The Scientist: Ancient organism, modern immunity
© A Quantum of Science / Peter Smalley (2009)
Reproduction with attribution is appreciation
New findings show adaptive immune system may not be new invention
Recently, scientists at Emory University in Atlanta reported that lampreys - a cartilaginous fish which evolved around 500 million years ago - is the oldest organism yet found to possess an adaptive immune system like that of humans. Previously, the adaptive immune system was believed to have originated in sharks, which evolved around 400 million years ago. This extra 100 million years is a big deal because the lamprey is a much earlier splinter from the vertebrate branch of the tree of life, and could mean that other even more ancient predecessors had already figured out how to "record" microbial invaders and repel them better in future infections.
Another interesting note: the age of cartilaginous fishes was known as the Silurian period, a time culminating in the so-called Law Event in which approximately 60% of aquatic species became extinct through a series of rapid climatic changes. Could the adaptive immune system have helped lampreys and sharks survive?
For more information:
The Scientist: Ancient organism, modern immunity
© A Quantum of Science / Peter Smalley (2009)
Reproduction with attribution is appreciation
Thursday, April 23, 2009
How now, brown cow?
A QUANTUM OF SCIENCE
What do cows now have in common with dogs, guinea pigs, armadillos, lemurs, the platypus, slime molds and wild mustard?
Bessie is the latest member in the club of organisms with sequenced genomes.
At present this club consists of approximately twenty single-celled organisms, twenty-two plants and thirty-six animals (not to mention 360 bacterial species). The club was founded in 1995 with the sequencing of the bacterium Haemophilus influenzae. Humans joined in 2000, fashionably late. The bovine genome has taken six years of work by 300 scientists at a cost of a quite modest $53 million (compared to the Human Genome Project at a bit over $3 billion). The project was spearheaded by researchers at Baylor College of Medicine in Houston, Texas and the results are provoking a level of interest far in excess of other organisms recently sequenced. The last "big" genome to be sequenced was the mouse, whose importance as a research tool can hardly be overstated. Almost all pharmaceuticals and therapies used on humans are tested on mice, so understanding their genetic variability was a huge milestone. So why is the cow genome making such a stir?
Unsurprisingly, it has to do with money. The cow is the first animal to be sequenced that has a significant commercial value associated with it. And ranchers and dairy farmers are already starting to queue up to have their herds genotyped, hoping to find out which ones carry genes associated with increased milk production, better tissue-building properties (read: faster meat) and improved resistance to pathogens. From a scientific basis this latter trait is among the most fascinating: even though cows diverged from the evolutionary tree before mice and well before humans, they share more genes in common with humans than they do with mice. In part this may be due to the far faster reproduction of mice giving them more generations to evolve, but there is some suggestion that humans and cows evolved more along similar tracks because of their symbiotic relationship over the last 10,000 years – in other words, domestication.
There were some definite surprises when the full map of the bovine DNA record was analyzed. Of particular note is the degree of repetition in their genome. Genes coding for immune defenses exist in myriad copies in the bovine genome compared to humans, perhaps due to the significantly greater exposure they have to microbes associated with digestion of cellulose. Curiously, the same thing may have caused cows to lose the genes for certain digestive enzymes from their genome that humans retained – since microbes were doing the digesting for them, cows did not need to retain those genes.
What good can come from this project? The significant benefit of knowing the blueprint for cows lies primarily in breeding. Currently most cattle breeding centers on bulls, and the cost to bring a single bull to an age where it can be bred is between $25,000 to $50,000 – and there are no guarantees a particular bull will make good breeding stock. Now, breeders can test bulls shortly after birth and determine which ones will make the best stock for particular desirable traits, saving tremendous amounts of money and making the process far less fraught with uncertainty and error. Best of all, breeding programs can now begin to reduce the dairy industry’s reliance on additives like rBST, the recombinant bovine somatotropin (better known as bovine growth hormone), a product used since 1993 as a means of increasing milk production but which has caused considerable controversy regarding the health of the animals in which it was used.
As a result of the sequencing of the bovine genome, the beef and dairy industries are poised for a potential rebirth as modern genetic techniques become available and better decisions can be made to improve the health of the industry, the consumer, and the cows.
For more information:
http://sciencenow.sciencemag.org/cgi/content/full/2009/423/2
http://en.wikipedia.org/wiki/List_of_sequenced_eukaryotic_genomes
© AQOS, Peter Smalley (2009)
Distribution with attribution is appreciation
What do cows now have in common with dogs, guinea pigs, armadillos, lemurs, the platypus, slime molds and wild mustard?
Bessie is the latest member in the club of organisms with sequenced genomes.
At present this club consists of approximately twenty single-celled organisms, twenty-two plants and thirty-six animals (not to mention 360 bacterial species). The club was founded in 1995 with the sequencing of the bacterium Haemophilus influenzae. Humans joined in 2000, fashionably late. The bovine genome has taken six years of work by 300 scientists at a cost of a quite modest $53 million (compared to the Human Genome Project at a bit over $3 billion). The project was spearheaded by researchers at Baylor College of Medicine in Houston, Texas and the results are provoking a level of interest far in excess of other organisms recently sequenced. The last "big" genome to be sequenced was the mouse, whose importance as a research tool can hardly be overstated. Almost all pharmaceuticals and therapies used on humans are tested on mice, so understanding their genetic variability was a huge milestone. So why is the cow genome making such a stir?
Unsurprisingly, it has to do with money. The cow is the first animal to be sequenced that has a significant commercial value associated with it. And ranchers and dairy farmers are already starting to queue up to have their herds genotyped, hoping to find out which ones carry genes associated with increased milk production, better tissue-building properties (read: faster meat) and improved resistance to pathogens. From a scientific basis this latter trait is among the most fascinating: even though cows diverged from the evolutionary tree before mice and well before humans, they share more genes in common with humans than they do with mice. In part this may be due to the far faster reproduction of mice giving them more generations to evolve, but there is some suggestion that humans and cows evolved more along similar tracks because of their symbiotic relationship over the last 10,000 years – in other words, domestication.
There were some definite surprises when the full map of the bovine DNA record was analyzed. Of particular note is the degree of repetition in their genome. Genes coding for immune defenses exist in myriad copies in the bovine genome compared to humans, perhaps due to the significantly greater exposure they have to microbes associated with digestion of cellulose. Curiously, the same thing may have caused cows to lose the genes for certain digestive enzymes from their genome that humans retained – since microbes were doing the digesting for them, cows did not need to retain those genes.
What good can come from this project? The significant benefit of knowing the blueprint for cows lies primarily in breeding. Currently most cattle breeding centers on bulls, and the cost to bring a single bull to an age where it can be bred is between $25,000 to $50,000 – and there are no guarantees a particular bull will make good breeding stock. Now, breeders can test bulls shortly after birth and determine which ones will make the best stock for particular desirable traits, saving tremendous amounts of money and making the process far less fraught with uncertainty and error. Best of all, breeding programs can now begin to reduce the dairy industry’s reliance on additives like rBST, the recombinant bovine somatotropin (better known as bovine growth hormone), a product used since 1993 as a means of increasing milk production but which has caused considerable controversy regarding the health of the animals in which it was used.
As a result of the sequencing of the bovine genome, the beef and dairy industries are poised for a potential rebirth as modern genetic techniques become available and better decisions can be made to improve the health of the industry, the consumer, and the cows.
For more information:
http://sciencenow.sciencemag.org/cgi/content/full/2009/423/2
http://en.wikipedia.org/wiki/List_of_sequenced_eukaryotic_genomes
© AQOS, Peter Smalley (2009)
Distribution with attribution is appreciation
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