Archive for the 'nature observations' Category

Published by Rosalind on 27 Jul 2010

Plastiki Arrives!

After 130 days at sea (and 8300 miles) the Plastiki arrived yesterday in Australia. The boat, made of more than 12,000 plastic bottles, sailed across the Pacific Ocean from San Francisco. The voyage was partly inspired by Thor Heyerdahl’s epic voyage on the raft Kon Tiki, when Heyerdahl tried to prove that ancient mariners could have traveled long distances without motors. Read about Plastiki’s arrival and visit the Plastiki site: The Plastiki.

Arriving in Sydney, Australia on July 26.

Published by Rosalind on 02 Apr 2010

Monarch Butterfly Update 2010

It hasn’t been a very good winter for Monarchs – bad weather seems to have taken a toll on them. Plan now to plant some milkweed for them and help the population recover. Read an update here: Monarch Butterflies . (Do you know how to tell the sex of Monarchs? The one in the picture is a male – you can tell by the dark spots on the inner wings. Those are the pheromone sacs, part of the way that the males communicate with female butterflies – by smell!)

monarch-butterfly_large

Published by Rosalind on 12 Jan 2010

Winter patterns

This NASA image shows the frozen Yukon River in Alaska.

This NASA image shows the frozen Yukon River in Alaska.

“Nature works in patterns, and one of those patterns is imprinted on the frozen Alaskan landscape in this true-color image from January 11, 2010. Like a winter-bare tree, a network of roots, or the veins, arteries, and capillaries that enclose an organ, the Yukon River branches across the snowy Yukon Delta to the Bering Sea.” As this NASA description says, we often see repeating patterns in nature. The bare branches of trees on a snowy winter day echo the frozen river and its tributaries…

This woodland stream still has enough open water to reflect the trees above.

An icy woodland stream still has enough open water to reflect the trees above.

Published by Rosalind on 27 Dec 2009

Satellite, satellite…

NASA’s Terra satellite has been orbiting for ten years, taking measurements of the earth with many sensors. People say, “A picture is worth a thousand words,” and these satellite images definitely fit the description. Right now, my house is in the snowy region of the Northeastern US. Looking at this image gives me a sense of sympathy for all the other folks in the wintry, snowy parts of the northern hemisphere — and it shows me where they are!

NASA satellite image of global snow cover, posted December 18, 2009

NASA satellite image of global snow cover, posted December 18, 2009

Check this link for more Terra images: Terra Turns Ten: snow, clouds and sunlight.

Published by Diana on 26 Nov 2009

Changes in organisms from natural selection

Over time, new kinds of organisms develop as a result of mutations and changes to existing organisms. Bacteria evolve resistance to antibiotics; the bacteria that aren’t resistant to antibiotics die off–and the very few that have a gene that makes them less likely to die are the only ones that live to reproduce. This process, in which better adapted organisms survive to reproduce and less adapted organisms die before reproducing (or have fewer offspring), is called natural selection and is the key concept of Charles Darwin’s theory of evolution.

Darwin published the first edition of his book on the evolution of species one hundred and fifty years ago, in November of 1859.

Darwin was curious about many things, and was interested in how land snails–like the European snail that ends up being eaten in the French dish escargot–could get to islands, because they don’t survive in salt water. After discovering that a short bath in salt water didn’t kill them, he decided that perhaps they got there on floating logs.

But more modern scientists have discovered that land snails come in right-handed and left-handed versions. The right-handed versions are more common, but there are more left-handed snails in Asia than elsewhere. Why? Well, it turns out that some snakes have evolved jaws that work better on the right-handed snails than on the left-handed ones. So as the right-handed snails get eaten more often, the left-handed snails are more likely to survive and reproduce, so there are more left-handed snails where there are more snakes that eat right-handed snails. Evolution and natural selection in action!

Read all about it here: In Snails and Snakes, Features to Delight Darwin.

Published by Rosalind on 03 Oct 2009

Not just the polar bears…

Scientists  working in the Arctic have found evidence that climate changes – particularly ice coverage – are having effects on the walrus populations there. The retreat of the sea ice, and the fact that fewer ice floes are available as nurseries for walrus pups, are causing difficulties for walruses. Biologists are beginning to consider whether the Pacific walrus should be named an endangered species. This article details some of what the researchers report: Walrus .

Published by Diana on 12 Jul 2009

Humans and Whales

In the mid-70s, the United States passed the Marine Mammal Protection Act, because the numbers of whales were declining all around the world. Whales were routinely hunted for food, for whale oil, for sport, and scientists were afraid they were going extinct. As time passed, a whale watching industry developed. The New York Times reports on human-whale interactions in this article:
Watching Whales Watching Us.

A small excerpt from the article:
“I read before my journey to Baja of what happens to people when they come in contact with a whale, how they tend to go, literally and figuratively, a bit overboard: nearly tipping over boats for a passing touch; spontaneously breaking into song; crying out in ecstasy; or just flat-out crying.”

Whales are enormous animals; their sheer size can be startling. When I was scuba-diving some years ago and we were lucky enough to encounter a juvenile humpback whale, it took me several moments before I could be sure what I was seeing. A thirty foot animal, especially one that is watching you as carefully as you are watching it, is huge and scary–and fascinating. The memory seared itself into my brain, and I can still see that young whale anytime I want, just by closing my eyes and remembering.

Published by Diana on 24 Jun 2009

You can’t make this stuff up

Snow rollers are a weird weather phenomenon that occurs only under perfect conditions. You have to have strong winds (but not too strong) and sticky snow (but not too sticky). They’re kind of a Goldilocks thing: everything has to be “just right.”

Check out this picture:

Snow Rollers, photo by Tim Tevebaugh

Snow Rollers, photo by Tim Tevebaugh

Further explanation can be found here: National Weather Service and Snow Rollers.

Published by Diana on 05 May 2009

Thinking About Bees

It’s been a cool spring where I live in the Pacific Northwest. The cherry trees are late this year, and the tulips are so late that the Skagit Valley Tulip Festival, scheduled for April 1st to April 30th, has been extended two weeks, well into May. The tulips weren’t really blooming this year until this week, I’m told by friends who went up last weekend.

The Northwest apricot trees are starting to bloom as well, and the growers are starting to move the bee hives into the field to pollinate the trees. Without bees, there would be very little fruit on the fruit trees here in the Northwest. We need bees to pollinate the apricots and peaches and (of course) the Washington apples for which we are famous. We need bees to pollinate the grapes that are made into Oregon’s wonderful pinot noir wines.

African Honeybees, Photo by Jay Torborg

African Honeybees (Photo by Jay Torborg)

In fact, bees (and a few other insects) pollinate pretty much all of our fruits, vegetables, and nuts. (Grains are mostly pollinated by wind.) This link lists the plants that are pollinated by bees: Crop Plants Pollinated by Bees.

Pollination occurs when a bee picks up pollen (from the stamens of the flower) when visiting a flower for its nectar. Then, when the bee flies to the next flower, some of the pollen falls off onto the stigma (or stigmas) of the flower. The pollen is comparable to sperm–it is the male gametes of the flower–and the stigma is a tube that leads directly to the “egg” of the female flower. (Some flowers are both male and female; some are male; some are female. It depends on the kind of plant it is. Plant sex is complicated.)

When the pollen grain lands on the stigma, it sends down a tube to the egg, then sends the DNA down to the tube, and the egg is fertilized.

Once the egg is fertilized, the egg produces a seed and the fruit around the seed. Imagine an apple. The whole apple is there just to persuade an animal to eat the seeds inside the apple. There is all that sweet fruit surrounding the seeds. So the animal eats the apple, and swallows the seeds, and they travel through the digestive tract, and are eventually eliminated, along with a nice bit of fertilizer. (From a plant’s point of view, an animal is just a really good way to get your seeds spread around.)

But without bees, there’d be no fruit.

So when bees are threatened, it’s a really big deal. A few years back, beekeepers discovered that their bees were dying in large numbers. It was called Colony Collapse Disorder and of course scientists started studying it.

Unfortunately, we don’t really know a lot about Colony Collapse Disorder yet, but there are a lot of theories about what to do about making sure we have pollinators. The New York Times had a great column about it a while back: Treatment for Bee Plague.

And researchers at Washington State University say it might not be that bad: Bee experts say Colony Collapse Disorder might not be as bad as first thought. (I have to say that traces of seventy different pesticides sounds pretty awful to me, though.)

What can you do? Plant food for your local bees. Don’t use pesticides.

(Honeybees are actually not native to this country. They were brought here by the first colonists, because they were considered essential. There are native bees that pollinate our native fruits and vegetables, but they need to be encouraged. In the meantime, beekeeping–maintaining hives of honeybees–is a huge business here in the United States. Half a million hives are brought into California every spring just to pollinate the almond trees so that we can all have almonds.)

There are other great websites for more information on bees and how you can help them in your garden! This website will tell you good plants to plant at home for bees: Bee Gardens.

This is a good place to learn more about Colony Collapse Disorder: Plan Bee Central.

Published by Diana on 17 Apr 2009

Bacteria are kind of amazing

Bacteria have found a way to live in almost every environment on our planet. They live in near-boiling hot mud pools at Yellowstone Park; they eat crude oil; they even, says this article: Iron Will to Live for Antarctic Microbes, live under Antarctic glaciers, in environments with almost no oxygen and no carbon.

Most organisms on our planet use respiration to provide energy for their internal functioning. In respiration, oxygen is used to burn carbon compounds (like sugars) to provide energy. Not these bacteria, which use sulfur-based compounds called sulfates.

If you look at the periodic table, you will see that sulfur falls just below oxygen, in the same column. Like carbon, it readily forms complex compounds that store energy. The Antarctic bacteria use iron found in the local rock to react with the sulfur compounds (called sulfates) and obtain energy through a different biochemical method.

Next »