Stories tagged Life Science


Brassinosteroids in tobacco plants: The level of brassinosteroids regulates both the size and aging of tobacco. With low levels, tobacco is dwarfed (some as small as 10 inches tall; see plant in front) and the leaves do not age, while at normal levels of brassinosteroids, tobacco stands almost 6 feet tall and the leaves turn yellow as they age (plant in back). Photo courtesy Michael Neff and Joanne Chory.

I am all over this idea. While I don’t personally mind mowing, I know lots of people do, and truthfully, while I don’t mind, I sure would like the additional free time!

In a paper in the May 4 issue of Nature, scientists from the Howard Hughes Medical Institute report that they have figured out a class of hormones that regulates growth in plants – including grass! And while this would be great for me, there are a lot of other good things that could come of this besides a mow-free yard, such as the development of trees that could be halted at a specific height so that they don’t interfere with power lines, raspberry bushes grown taller so that they are easier to pick, and increase the yields of crops such as corn or soybeans.

The key hormones are called brassinosteroids. With this new knowledge regarding brassinosteroids scientists may be able to stop growth in yard grass by limiting brassinosteroids or increase the yield of a crop by increasing brassinosteroids. Increasing crop yields would be very useful, especially considering urban expansion and the loss of farmland worldwide and steadily increasing global populations.

I can’t wait until the mow-free lawn becomes a product – but we’re likely many years away from that happening. Until then, I’ll keep mowing – or just replace my lawn with Field Turf.


After all the rain we've had recently, parents of toddlers in the Twin Cities area surely have two questions on their minds:

  • Will this rain EVER stop? Or, more accurately, will this rain PLEASE let up before I'd rather lie down and get eaten by bears then spend one more second cooped up in the house with my two-year-old?
  • And why are there worms all over the sidewalk whenever it rains?

I can't help with the first question.
But the second, that's a topic for Science Buzz!

I always thought that the worms came out of the ground when it rained to avoid being drowned in their burrows. Turns out I was wrong, wrong, wrong.

A series of Straight Dope articles, by Cecil Adams, have enlightened me.

Worm: (Photo by Jiva)

Turns out that the worms are in no danger of drowning. They can actually survive underwater for quite a long time. They are out on the sidewalk after it rains to engage in, um, "amorous activity." For the slimy details, read the Adams' column!

Of course, that's not ALL the worms are doing. They're also trying to move safely to new areas; vulnerable to drying out as they are, they can only do this aboveground at night or after a rain.

My toddler will be blown away by all this. Her explanation is that worms come out because of some altruistic notion that robins are hungry...

For more information about earthworms, check out this JourneyNorth Q&A page.


UPDATE - Wednesday, June 14th

One of the falcon chicks spent part of the day learning to fly. The others are doing a lot of looking and wing-flapping, and will be joining their nestmate soon.

Peregrine chicks: Photo taken by the High Bridge web cam between 8 and 9 am, Friday, June 9.
Peregrine chicks: Photo taken by the High Bridge web cam between 8 and 9 am, Friday, June 9.

UPDATE - Friday., June 9th

The little fluffballs are gaining feathers fast and looking more like adult peregrines every day. They've been flapping their wings and looking over the edge a lot. We expect them to fledge--leave the nest--sometime before June 16. See today's comment for more information.

All four chicks have hatched!: Yeah! Four hungry mouths to feed.

UPDATE - Friday., May 5th

All four of Athena's chicks have hatched now! Congratulations to Athena and her new Peregrine Falcon family. As far as we can tell from the pictures the fourth egg must have hatched around 5pm yesterday, Thur. May 4th.

One more to go: Athena seems to look straight at the camera and we have only one more egg to hatch.Courtesy Excel energy

UPDATE - Thu., May 4th

Three of Athena's chicks have hatched and you can see them crowding around the one brown egg that hasn't hatched yet.

Three mouths to feed: One of Athena's chicks raises its mouth for food, Thur. morning.

Wed., May 3rd

Athena can be seen feeding two of her chicks on Xcel's Falcon Cam. You can keep updated by watching the new pictures appear every couple minutes in the daily photos section.

Athena feeding her chicks: Check out Athena droping food into her little chicks' mouths. So cute!

Update from atop the giant smokestack at the High Bridge power plant here in Saint Paul and down the street from the Science Museum:

"Athena's" eggs have started to hatch.


Beaver: Castorocauda lutrasimilis life reconstruction. The artwork of the reconstructed animal is 50% of actual fossil size. Illustration: Mark A. Klingler/CMNH
Most early fossil mammals were tiny, rodent-like, and ate primarily insects. Paleontologists assumed that mammals didn’t diversify much or grow to large sizes until their dinosaurian competition was eliminated. Recent fossil finds from China have included larger early mammals that have changed this view of mammal evolution. And now, with the new discovery of the beaver-like Castorocauda lutrasimilis, we know that a hefty mammal (about a half-meter long) evolved to live a semi-aquatic lifestyle way back in the Jurassic Period, a time on earth best known for enormous dinosaurs!

Assembly by committee?
Castorocauda is not directly related to any modern mammals. But it resembles several! Castorocauda looks like a combination of otter, beaver, and platypus. With webbed hind feet and a scaly paddle-shaped tail, Castorocauda was clearly a semi-aquatic animal. This early mammal ate more than just insects. Its seal-like teeth suggest it ate fish. Other aquatic mammals aren’t found in the fossil record until many millions of years later, making Castorocauda the first of its kind.

Record for the oldest fur pelt
Early fossil mammals are known primarily from their teeth. Other skeletal remains are rare. Castorocauda has a near-complete skeleton and its fur was remarkably fossilized, too! The fossil fur is similar to that of modern mammals that have adapted to swimming in cold water. At 164 million years old, this fur is the oldest ever discovered.


Spotted Owl: Spotted owl (Courtesy John and Karen Hollingsworth, US Fish and Wildlife Service)
Spotted Owl: Spotted owl (Courtesy John and Karen Hollingsworth, US Fish and Wildlife Service)
Remember the spotted owl? Back in the 80s and 90s, the spotted owl was in the news quite a bit when it was designated an endangered species and its habitat, the old-growth forests of the Pacific Northwest, was protected. Given that the habitat of the spotted owl was also the source of income for a large number of people in the region, environmentalists, politicians, and area residents squared off. It was, and continues to be, a contentious issue. While protecting the habitat of the spotted owl makes sense, does it continue to make sense if it is at the expense of the livelihoods of hundreds of families? This issue is discussed in detail in the Hunters of the Sky exhibition, which will be at the Science Museum this fall.

The spotted owl made news again recently, this time because US Fish and Wildlife service had planned to hire a contractor to develop a recovery plan for the spotted owl, but due to federal budget cuts now finds that it will have to develop the plan on its own. Seems weird to me that this would be something that the US Fish and Wildlife would contract out, and it also seems weird that a plan for the species had not even been developed yet. I know that the issue is controversial, but it has been over 15 years since the owl was designated an endangered species – it would seem that a plan for saving an animal from extinction would be something that would need to be developed quickly. However, lawsuits have kept the plan in limbo while the spotted owl population continues to dwindle through loss of habitat from wildfires, disease, and competition from the barred owl for nests. The decision could be made for us if something is not done soon.


Humpback Whale: A Humpback Whale dives beneath the surface Courtesy NOAA

Scientists Ryuji Suzuki, John Buck, and Peter Tyack used information theory to prove that humpback whale songs have syntax--rules that govern the structure of language.

Like humans, the whales use a hierarchy of communication: they make sounds to build phrases that they can combine in different ways to create songs that last for hours.

The scientists wrote a computer program that breaks down the elements of the whales' songs (moans, cries, and chirps) and assigns a symbol to each one. Then they analyzed the structure of the songs.

Suzuki says,

"Information theory was the right choice because it allows one to study the structure of humpback songs without knowing what they mean."

Sight and smell are limited in marine environments, so sea mammals often use sound to communicate. During the humpback whale breeding season, all the males in a population sing the same song. And the song evolves over time.

Suzuki says,

"Humpback songs are not like human language, but elements of language are seen in their songs."


Wolf: Image courtesy International Wolf Center.

Yesterday the Science Museum of Minnesota opened a small traveling exhibition called Living With Wolves in the 21st Century that compares the wolves of North America within a world perspective and examine ways humans determine wolf survival. Coincidentally, yesterday U.S. Interior Secretary Gale Norton initiated a federal plan to move the management of gray wolves in Minnesota and other Great Lakes states to tribal and state agencies. In addition, the U.S. Fish and Wildlife Service has begun the process of taking wolves off the endangered species list in Minnesota, Michigan and Wisconsin, as well as in parts of North Dakota, South Dakota, Iowa, Illinois, Indiana and Ohio, because their populations have recovered under the federal protection of the Endangered Species Act.

The U.S. Fish and Wildlife Service estimates that there are nearly 4,000 gray wolves in Minnesota, Michigan and Wisconsin, which is up from between 700 and 1,000 when the gray wolf was listed as endangered in 1974.

Read the press release from the U.S. Fish and Wildlife Service for more information. Comments on this proposal can be submitted by e-mail to [email protected]


Peregrine Falcon: Peregrine Falcon.  Courtesy Craig Koppie, US Fish and Wildlife Service.
Peregrine Falcon: Peregrine Falcon. Courtesy Craig Koppie, US Fish and Wildlife Service.

The peregrine falcons at the High Bridge power plant usually lay eggs in mid- to late March. The female lays one egg every 2 to 3 days, with an average total clutch of 3 to 4 eggs. It's 33 to 35 days until the eggs hatch; during that time, the female spends most of the time on the nest incubating the eggs and the male does most of the hunting and brings her food.

Once the young hatch, the female cares for them continuously for the first few days and then her attention slowly wanes as the chicks get stronger. The chicks will remain in the nest for 35 to 42 days after hatching. At some point during this time the chicks will be banded with their identification number and name them so they can be tracked in the future.

And this is where you come in. Submit your ideas for names for the potential falcon chicks at the High Bridge power plant in the comment section below. (Names can't be reused, so we've provided a list of those already taken.) If the falcons produce a clutch of eggs, we'll select the best names from your submissions and post them in a poll for everyone to vote on in a few weeks. The top vote getters in the poll will be the names given to any chicks that survive and are banded.

So — what do you think? What's a good name for a falcon? Don't forget to check the polls page in a few weeks to see what names have been selected and vote for the best one!

Here are the names that are already taken:

Abby, Alice, Allie, Alpha, Amanda, Amilia, Amy, Andrea, Andy, Angel, Anton, Apryl, Barbara, Belinda, Ben, Berger, Bern, Bert, Bertha, Beta, Bolt, Bomber, Bor, Brice, Britta, Burt, Buzz, Candy, Cassie, Charlee, Charlie, Cherokee, Chicklet, Chris, Cleo, CoCo, Cole, Colleen, Coz, Craig, Crystal, Cyndi, Dale, Dana, Danberg, Davey, Dawn, Delene, Delta, Diamond, Diana, Diane, Dick, Dixie Chick, Donna, Doolittle, Dot, Ed, Eileen, Elaine, Electra, Esperanza, Faith, Fast Track, Fluffy, Fran, Frank, Gamma, George, Gib, Gloria, Gold, Gretta, Grunwald, Harmony, Hickey, Hippie, Hope, Horus, Hotshot, Howard, Hunter, Huske, Irvine, Isabel, Jackie, Jacob, Jan, Janice, Jasmine, Jay, JB, Jenny, Jessy, Jim, Joe, Joe, Judy, Julie, Kali, Karlsen, Katraka, Kester, Kitty, Kody, Kramer, Krista, Laura, Leo, Leon, Leona, Leonardo, Liberty, Lightning, Lily, Linton, Lolo, Lon, Lora, Loree, Loretta, Lori, Louise, Lucky, Mac, Maggie, Malin, Manthey, Mapper, Marie, Marshall, Marty, Mary, Maude, Mew, Mica, Michael, Michelle, Minnie, Miranda, Miss, Miss Pam, Mulder, Murphy, Neil, Nero, Nicole, Nora, Oar, Orville, Oscar, Pam, Pamella, PF Flyer, Pathfinder, Penelope, Penny, Phyllis, Polly, Porky, Prescott, Princess, Putnam, Quark, Queen, Rachael, Ralph, Razor, Red Ed, Rick, Rochelle, Rocket, Rocky, Romeo, Ryan, Ryu, Sarah, Scarlet, Screech, Scully, Seminoe, Shakespeare, Sharky, Sheri, Sheridan, Sherlie, Smoke, Smokey, Sonic, Sophia, Speedy, Spider, Spirit, Spivvy, Static, Stephanie, Sue, Survivor, Swoop, Terri, Thelma, Thunder, Travis, Tundra, Vector, VernaMae, Veronica, Waldo, Wanda, Warren, Wayne, Webster, Wilbur, Willie, Wood, Younger, Zack, Zippidy


A study back in 2004 found that the avian flu (H5N1 virus) can also infect cats, and that cats can spread the flu to other cats. A dead cat in Germany this past weekend has been found to have had been infected with the H5N1 virus. It is believed that the cat contracted the virus after eating an infected bird, which is in line with the pattern of disease transmission in Asia. This was the first case of the H5N1 virus being found in a mammal in Europe. If the virus can be transmitted to cats can it be transmitted to other mammals, like humans?

One mammal that scientists are particularly worried about becoming infected by the H5N1 virus is the pig. Since pigs can be infected with the human flu virus, there is concern that if a pig were to become infected with both viruses they could combine to create a new virus that would be transmittable to people.

Check out this interactive map to see how far and fast the virus is spreading. Learn more about the avian flu here at Science Buzz by visiting Liza's blog on the avian flu or our online avian flu exhibit.


The Science Museum's neighbor, the Xcel Energy High Bridge power plant, will be undergoing a significant construction project in the coming months. As part of a larger project called Metro Emissions Reduction Project (MERP) Xcel Energy has started working on a $1 billion program that will reduce emissions from three metro area plants (the High Bridge Plant being one) and increase power generating capacity.

Generator: Working principle of a combined cycle power plant.Courtesy Alureiter

Xcel - Current: Existing High Bridge plant. Image courtsey Xcel Energy.

The High Bridge power plant is being converted from a coal burning plant to a combined-cycle natural gas plant. Combined power plants generate electricity from two sources - a gas turbine generator that is powered by natural gas and a steam turbine generator that is powered by the heat exhaust from the gas turbine generator. This use of the gas to essentially power two different types of generators is a more efficient use of resources than the coal burning power plant. As a result of this change, air emissions from the High Bridge power plant will be significantly reduced. Sulfur dioxide emissions will be reduced 99.7%, nitrogen oxide 96.9% and particulate matter 91.5%, while mercury pollution will be completely eliminated.

Xcel - New: High Bridge plant after construction is complete - artist's rendition courtsey Xcel Energy.

My first thought after hearing this (and after having to put gas in my car and heat my home the past few months) was that switching to natural gas is not a very economical situation given current gas prices. However, Xcel says that:

Although natural gas prices have increased, this conversion makes sense for the long term. The gas market is subject to short-term volatility, but the plants will operate for another 30 years so it's the long-term projections that are most important.

If you are in the downtown area in the coming weeks you may hear construction noise from the site as the nearly 1,200 steel pilings for the new power plant are driven into the ground for the new plant's footings. Testing of the new power plant will begin around September 2007 and run through March 2008. The plant is expected to begin commercial operation in May 2008, and demolition of the old plant will start shortly thereafter.

For more information visit Xcel Energy's web pages on the conversion.