Archive | November 2014

3 Things You Probably Didn’t Know about Turkey

The Merriam’s subspecies of wild turkey. Photo by Dan Garber, Smithsonian Institution.

The Merriam’s subspecies of wild turkey. Photo by Dan Garber, Smithsonian Institution.

This Thanksgiving, millions of Americans will once again head over the river and through the woods—or onto the interstates and jam-packed jets, as the case may be. Millions more will stay home to host family and friends. Most will likely serve turkey. After all, it’s America’s traditional Thanksgiving entrée.

A few months ago, I had the pleasure of interviewing Julie Long, a scientist with the U.S. Department of Agriculture’s Agricultural Research Service. In the spirit of the Thanksgiving holiday, here are three things Long shared that you probably didn’t know about turkey.

  1. There may no longer be any populations of the wild turkey that was the ancestor of the turkey most Americans will eat this Thanksgiving.

Long and other scientists from USDA, the Netherlands’ Wageningen University, and the Smithsonian Conservation Biology Institute determined that the ancestor of today’s Thanksgiving dinner turkeys was most likely a wild turkey from Mexico.

However, the only place the team could find that turkey was as a preserved specimen at the Smithsonian Institution. And that turkey was genetically distinct from today’s wild turkeys.

“The wild birds that are in North America are not genetically related to the commercial breeds that we eat,” Long says. The team published its findings in BMC Genomics in 2012.

Apparently, early Spanish explorers took the ancestral birds back to Europe. Farmers there developed different breeds. Later, English colonists brought domesticated turkeys with them to Jamestown. So much for a totally “American” tradition.

  1. Although many media photos of live turkeys show brown birds, the turkey on most Americans’ tables this Thanksgiving will have had white feathers.

Brown turkeys are tasty and edible. But they probably wouldn’t look that good to most Americans.

“At the tip of every feather that’s colored, there’s a bit of pigment in the skin,” Long explains.

That pigment causes dark spots on the skin. Rather than educate people about the meat’s wholesomeness, commercial turkey breeders just raise white turkeys instead.

  1. All turkeys for large-scale U.S. commercial operations must be artificially inseminated.

In a quest to get the most white meat per turkey at the lowest cost, farmers have bred turkeys to have “enormous breasts,” says Long. “A male turkey can up to get up to 70 or 80 pounds when they’re mature,” says Long.

However, those big-breasted males “physically can’t get where they need to be,” Long says. As a result, farmers need to help them along with artificial means. Because of poultry’s biology, however, achieving high rates of success is more difficult than it is for mammals.

I’m thankful that Long shared these insights with me, along with lots of other fascinating information for the article I was preparing at the time. That piece should be out this winter.

More generally, I’m grateful for all the patience and courtesies that researchers show to me throughout the year so I can better understand and write about science. And I’m thankful for readers who enjoy this blog, along with my books and articles for a variety of outlets.

Here’s hoping everyone has a blessed and wonderful Thanksgiving!

 

 

Sleeping Like a Baby

Photo (c) Kathiann M. Kowalski

Photo (c) Kathiann M. Kowalski

Everyone knows newborn babies sleep a lot. At least, that’s what the books say–although many sleep-deprived parents might disagree. But why?

Scientists have mounting evidence to support the idea that sleep is necessary for effective learning and memory functions. Other research links lack of sleep to increased risks for different types of mental disease.

Now new research adds additional support for the broader idea that researcher Howard Roffwarg and his colleagues suggested as early as 1966–that infant sleep might help in the structural maturation of circuits in the central nervous system.

The new study shows those circuits aren’t limited to those needed for learning and memory. Moreover, the effects of sleep deprivation could last much longer than we think. Amita Sehgal of the University of Pennsylvania presented the research at the Society for Neuroscience’s 2014 annual meeting.

Sehgal first described how fruit flies are a useful model for sleep research. For starters, they’re practical. Fruit flies are cheap to use and breed in large numbers.

Second, fruit flies have many of the same behaviors that mammals do. And yes, fruit flies actually sleep.

Fruit flies have a simpler anatomy than mammals, however. As a result, it’s easier for researchers to do dissections and identify interactions in their central nervous systems.

And beyond all of this, fruit flies are useful for forward genetics work. They have distinct mutant phenotypes with less redundancy and compensation. Modify the genetic makeup, and the fruit fly usually won’t be able to make up for the change with other mechanisms. With these factors in mind, researchers have developed several specific strains of fruit flies to have particular characteristics.

The research team explored how differences in fruit flies’ neurotransmitter levels affected different aspects of sleep, such as difficulty in arousing them from sleep or “rebound” after a period of sleep deprivation.

Researchers also looked at fruit flies’ behavior. In particular, the team found that particular scent pathways that are necessary for effective courtship behavior did not function properly in mature flies if they had been deprived of sleep after being newly hatched.  Sehgal and her colleagues Matthew Kayser and Zhifeng Yue published the research in the journal Science in April 2014.

Last month, Senator Rand Paul (R-KY) ranted about NIH funding research “to discover whether or not male fruit flies would like to consort with younger female fruit flies.” Sehgal said yes, her group’s research was what Rand was referring to.

But the study wasn’t about sex, she stressed. And while the study was done with fruit flies, their importance as an animal model means that human researchers can learn a lot from the results.

Bottom line: Much more happens in newborn sleep than we realize. And scientists now have measurable evidence to document some of what’s going on.

Of course, much more work remains to be done. Maybe some of today’s newborns will one day add to the growing body of scientific knowledge and understanding about the brain.

And maybe their parents will get to catch up on some sleep.

 

What’s for Lunch?

Food service workers prepare meals for the school lunch program. Photo by Ken Hammond, USDA Agricultural Research Service Image Library, Image 03CN0713-4.

Food service workers prepare meals for the school lunch program. Photo by Ken Hammond, USDA Agricultural Research Service Image Library, Image 03CN0713-4.

What’s on your child’s lunch tray? It depends on whether your child packs lunch or buys the full meal deal available under the National School Lunch Program.

Either way, the meal probably meets nutrition standards “almost entirely,” says Alisha Farris, lead author of a new study at Virginia Tech. The report appears in the November/December issue of the Journal of Nutrition Education and Behavior, published by Elsevier.

Lunches brought from home were more likely to exceed recommendations for fat and saturated fat. They were also more likely to have dessert items, savory snacks, and sugar-sweetened drinks.

The researchers examined both types of school lunches for kids in preschool and kindergarten after implementation of the 2012-2013 National School Lunch Program standards. The results are mostly consistent with earlier studies that compared school lunch program and packed lunches for different grade levels.

“This is consistent with what we have seen,” says Beth Spinks, a registered dietitian and director of nutrition services for the Berea City School District in Ohio.

Yet while packed lunches on average came close to meeting nutrition standards, there was still a lot of variation in what was in those lunches. At one point Spinks asked a grad student to evaluate packed lunches brought by fifth graders in that school district.

“They were all over the place in nutrients,” Spinks says. Indeed, some lunches packed by students themselves “just had chips and cookies.”

To the extent school lunches fell short in the Virginia Tech study, it was generally on the energy and iron recommendations. When it comes to calories, kids don’t have to take all the items offered by school meal plans, and researchers were focusing on what kids actually had on their trays.

Just having food on their trays isn’t enough, though. Kids actually have to eat the food to get the nutritional value, and the Virginia Tech team recognized this as a limitation in their study. Thus, one recommendation it makes for future studies is to gather food waste data and compare consumption for packed and school lunches.

Spinks agrees this would be worthwhile.

“When we watch the garbage cans, we see a lot of food from both the packed and purchased lunches being thrown away,” she says. “We need to figure out why. Planning a great lunch does nothing if the child does not eat it.”

Meanwhile, the study could be helpful to promote school meals and give parents suggestions for packing lunches, she notes.

And nutrition isn’t the only thing parents should focus on if they pack lunches for themselves or children. Food safety matters too, stresses Spinks.

Now there’s another topic for research….