Category Archives: Life Science

Birds Fly Early

Spring Is Early, and So Are the Birds, NPR webcast

This is short real life example of the scientific method. Spring is coming earlier to Europe, thanks to global warming. Scientists figured migrating birds in southern Europe would be able to adjust to the change and leave early (because the early warming would also be obvious where they wintered). But the scientists expected that birds from Africa would not be able to tell that they should leave early.

However, they studied what actual took place and found that the migrating birds from Africa were actually arriving early while those in southern Europe were not. So now they are revising their theories and will do more study to try and determine what is happening and why (for example, how are the birds in Africa deciding to leave early?).

Swimming Robot Aids Researchers

Swimming Robot

Swimming Robot Tests Theories About Locomotion in Existing and Extinct Animals

An underwater robot is helping scientists understand why four-flippered animals such as penguins, sea turtles and seals use only two of their limbs for propulsion, whereas their long-extinct ancestors seemed to have used all four.

Don’t miss the video of the robot swimming and an informative interview with professor, John H. Long, Jr., Ph.D., who is researching with the robot.

Open-Source Biotech

Open-Source Biotech:

Mr. Jefferson, the man credited with inventing one of the main tools used in plant genetic engineering, started his campaign in 1987 by doing what the big companies that dominate agricultural biotech rarely do: He shared his discovery of beta-glucuronidase gene (GUS), an indicator that tells where a gene is, how much it expresses, and when it acts.

GUS is widely credited for enabling many breakthroughs in plant biotech, including the development of one of Monsanto’s first and most profitable agricultural products, Roundup Ready soybeans. Mr. Jefferson first provided GUS and all the know-how to use it for free to hundreds of labs around the world.

When he secured his patents, he charged only what people could afford: Monsanto, he says, paid a substantial amount; academics and companies in the developing world, including those who wanted to use his work for commercial purposes, received it free of charge.

Continue reading →

Bacterial Evolution in Yogurt

Adapting to Life in Yogurt by Carl Zimmer:

The analysis, based on the microbe’s newly sequenced genome, suggests that the bacteria descend from microbes that originally fed on plants. Some of them fell accidentally into some herder’s milk, it seems, and happened to clot it and kept it from spoiling. Since then, people have been transferring yogurt to fresh milk time and again, and the effect has been like running a long-term experiment on the evolution of bacteria.

Carl Zimmer provide much more detail in this podcast: evolution of bacteria in yogurt. Continue reading →

The Art and Science of Imaging

Cancer Cell

The Art of Imaging from Invitrogen (via Molecular Probes’ protocols for pretty pictures). See interesting images and details on exactly how to scientists create such images.

image: -catenin in HeLa human cervical cancer cells was labeled using mouse anti–catenin and visualized with Alexa Fluor 488 goat anti-mouse IgG (green). Filamentous actin was visualized using red-fluorescent Alexa Fluor 635 phalloidin. Nuclear DNA was stained with blue-fluorescent DAPI. Larger photo and more details

The image gallery includes many more images.

Arctic Seed Vault

Work begins on Arctic seed vault:

More than 100 countries have backed the vault, which will store seeds, packaged in foil, at sub-zero temperatures.
…
The vault’s purpose is to ensure survival of crop diversity in the event of plant epidemics, nuclear war, natural disasters or climate change; and to offer the world a chance to restart growth of food crops that may have been wiped out.

At temperatures of minus 18C (minus 0.4F), the seeds could last hundreds, even thousands, of years. Even if all cooling systems failed, explained Mr Riis-Johansen, the temperature in the frozen mountain would never rise above freezing due to the permafrost on the mountainside.

Gecko Tape

Sticking Around with Gecko Tape:

The tape is a simple version of the adhesive on a gecko’s feet. The soles of the lizard’s feet are covered with millions of tiny little hairs, too small to see with the naked eye. The molecules in these hairs snuggle up to the molecules of any surface the gecko walks on. The molecules are attracted to each other, forming a temporary bond that keeps the gecko firmly in place.

Also see, Caught on tape: Gecko-inspired adhesive is superstrong, for more details.

Photo: An array of tiny plastic pegs mimics the microscopic structure of a gecko’s sticky sole.

Two Butterfly Species Evolved Into Third

Butterfly photo

Two Butterfly Species Evolved Into Third, Study Finds by James Owen, National Geographic News:

Researchers say their creation reveals a process called hybrid speciation, in which the genes of two existing species combine to produce a third.

The study suggests hybridization may be more important to the evolution of new animals than had previously been thought.

Hybrids such as the mule, a cross between a donkey and a horse, are sterile. But the team says the butterfly hybrid brought together a combination of genes that allowed it to breed and there be considered a new species.

Biological Molecular Motors

bio

Image: The biomolecular portal motor of bacteriophage PHI-29 (yellow) compresses the coiled DNA into the viral capsid at 6,000 times its normal pressure. (courtesy the Bustamante group)

Start Your Protein Engines by David Pescovitz:

Oster and his research group investigate the physics and chemistry behind great engineering mysteries of the natural world, from protein motors to cell motility to how bacteria form thriving populations that aren’t so different from ant colonies, or even human societies.
…
Working with UC Berkeley professor Carlos Bustamante, researchers have also studied the motor that packs a virus’s DNA so tightly that it can be injected into a hijacked cell at ten times the pressure of a cork shooting out of a champagne bottle. And they’ve modeled the donut-shaped molecular motors that move along DNA strands during replication.

In the closing paragraph Dr. Oster is quoted on the use of models, which reminds me a the quote from Dr. George Box: All models are wrong, some are useful.

Other articles from from the most recent ScienceMatters@Berkeley: The New New Math of String Theory and Molecular Rules Of Engagement. Also see previous article: The Cellular Mechanic.

Cancer Scientists Find Worm Link

Cancer scientists find worm link by Matt McGrath:

Now scientists in California have found that when they removed this same protein from the tiny worm C. elegans, the worms lived up to 30% longer than normal.

The scientists deduced that a lack of this protein might mean that humans also live longer, but with an increased risk of getting cancer.

The researchers think the protein’s dual function raises another important question: does the presence of this protein ensure a short but cancer-free existence for some people?