Is it just Shark Week, or did thresher sharks get smarter?

Divers off the coast of Cebu, an island in the Philippines, called Simon Oliver when they noticed sharks exhibiting some strange behavior.

Oliver, an expert on these sharks since he began studying them in 2005, dropped everything to see what all the fuss was about. Apparently they were using their tails to hunt—strange behavior because it was thought that only smart mammals like dolphins and whales practiced tactical use of the tail fin.

Equipped with underwater camera equipment, the Thresher Shark Research and Conservation Project set out to film the new shark activity. They captured footage of 25 hunting events, then went back to the lab to analyze the videos.

The researchers found that the sharks hunt schooling sardines using a four-step procedure. This way, instead of collecting just one fish in their mouth per hunting event, they first stun the fish to eat an average of 3.5 sardines.

Thresher sharks’ tails comprise about 50% of their total length, which is particularly impressive for the 20-foot, 1,000-pound individuals. A sardine lucky enough to survive its initial fear would witness an incredible “tail-slap,” only to die or become stunned shortly after.

First the shark prepares. This preparatory lunge lasts longer than the other three phases, allowing the shark to perform some advanced physics calculations in order to determine tail velocity needed based on mass… Just kidding, they aren’t that smart! The shark then strikes, recovers briefly, and collects its prey.

“This extraordinary story highlights the diversity of shark hunting strategies in an ocean where top predators are forced to adapt to the complex evasion behaviors of their ever declining prey,” said Oliver.

These sharks had been studied previously, but Oliver thinks that lack of food has caused the sharks to hunt near the surface, finally giving humans a glimpse of their unique hunting techniques.

The footage is pretty incredible, and you can check it out here!

Alyssa Keimach is an astronomy and astrophysics student at the University of Michigan and interns for the Morrison Planetarium.

Using satellite data from NASA’s Solar Radiation and Climate Experiment (SORCE) satellite, researchers found that between 2004 and 2007, low solar activity actually resulted in more energy and visible light reaching the Earth, warming our climate. The findings are published today in the journal Nature.

Solar activity increases and decreases over a cycle that lasts roughly 11 years. Even after centuries of study, we have only begun to get a complete picture of the process. From a corresponding article in Nature:

Sunspots, dark areas of reduced surface temperature on the Sun caused by intense magnetic activity, are the best-known visible manifestation of the 11-year solar cycle. They have been regularly observed and recorded since the dawn of modern astronomy in the seventeenth century. But measurements of the wavelengths of solar radiation have until now been scant.

Instruments on the SORCE satellite measure the Sun’s energy output at many different wavelengths of light. Researchers fed the data from SORCE into an existing computer model of Earth’s atmosphere and compared their results with the results obtained using earlier, less comprehensive, data on the solar spectrum.

And the results were shocking. From New Scientist:

Previous studies have shown that Earth is normally cooler during solar minima. Yet the model suggested that more solar energy reached the planet’s surface during the period, warming it by about 0.05°C.

This surprising finding led the researchers to believe that the inverse might also be true: in periods when the Sun’s activity increases, it might tend to cool, rather than warm, Earth. But, they warn, more data are needed.

Joanna Haigh, an atmospheric physicist at Imperial College London and lead author of the study, said:

These results are challenging what we thought we knew about the Sun’s effect on our climate. However, they only show us a snapshot of the Sun’s activity and its behavior over the three years of our study could be an anomaly.

We cannot jump to any conclusions based on what we have found during this comparatively short period and we need to carry out further studies to explore the Sun’s activity, and the patterns that we have uncovered, on longer timescales. However, if further studies find the same pattern over a longer period of time, this could suggest that we may have overestimated the Sun’s role in warming the planet, rather than underestimating it.

In addition, Martin Dameris, an atmospheric scientist at the German Aerospace Center, warns that human activity still lies at the heart of our current warming trend. As quoted in the Nature article:

The findings could prove very significant when it comes to understanding, and quantifying, natural climate fluctuations. But no matter how you look at it, the Sun’s influence on current climate change is at best a small natural add-on to man-made greenhouse warming.

Auroras

National Geographic had some great images of the auroras that came out of the solar activity on August 1st.

WISE Losing its Cool

Universe Today reported this week that the WISE satellite only has a few more months of operation:

The spacecraft is running out of the frozen coolant needed to keep its heat-sensitive instrument chilled, and will only be in operation for 2-3 more months. While the spacecraft was designed to be rather short-lived – 7 to 10 months — it still is sad to see the mission winding down.

Alternative Energy Bonanza

We reported on renewable energy in the news earlier this week, and today, Science magazine devotes an entire special issue to clean energy. Even if you don’t have a subscription, you can download the entire section for free before the end of the month.

Frog Hunt

Earlier this week, news outlets reported a new search for amphibians, organized by Conservation International, that will take place over the next two months. From Wired:

Scientists in 14 countries on five continents are teaming up to hunt for as many as 100 species of amphibians that are thought to possibly be extinct, but may be surviving in remote corners.

We’ll stay tuned to see what they discover…

Climate

Climate was covered in many news items from the floods in Pakistan to the fires in Russia to the all-time heat records worldwide to the iceberg that broke away from Greenland. From the Huffington Post:

No one knows for sure whether any of these natural disasters — with the possible exception of the floating iceberg — are directly traceable to climate change, but they are certainly consistent with climate change forecasts. And, if they are, they clearly suggest that more records and more disasters are on the horizon.

What did you find interesting in science news this week? Why? Share with us.