Earthquakes at 2 Alaska Volcanoes Could Signal Eruption

In this photo provided by the Alaska Volcano Observatory/US Geological Survey is the Tanaga Volcano near Adak, Alaska, on May 23, 2021. (Alaska Volcano Observatory/US Geological Survey via AP)
In this photo provided by the Alaska Volcano Observatory/US Geological Survey is the Tanaga Volcano near Adak, Alaska, on May 23, 2021. (Alaska Volcano Observatory/US Geological Survey via AP)
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Earthquakes at 2 Alaska Volcanoes Could Signal Eruption

In this photo provided by the Alaska Volcano Observatory/US Geological Survey is the Tanaga Volcano near Adak, Alaska, on May 23, 2021. (Alaska Volcano Observatory/US Geological Survey via AP)
In this photo provided by the Alaska Volcano Observatory/US Geological Survey is the Tanaga Volcano near Adak, Alaska, on May 23, 2021. (Alaska Volcano Observatory/US Geological Survey via AP)

A second volcano in remote Alaska is experiencing elevated earthquake activity this week, signaling an increased potential for eruption, officials said.

Earthquake activity near Takawangha Volcano increased over the past 48 hours and are continuing, Alaska Volcano Observatory officials said in a news release Thursday.

That volcano is west of Anchorage in the western Aleutian islands and about 5 miles (8 kilometers) from Tanaga Volcano, which scientists said earlier this week had seen intensified earthquake activity.

The Alaska Volcano Observatory raised the alert level to advisory status for Tanaga Volcano late Tuesday after the quakes became vigorous.

The observatory on Thursday raised the alert level to watch status for Takawangha Volcano.

Analysts at the observatory continue to monitor the situation closely. Up to several earthquakes per minute are occurring under Tanaga Island, where both volcanoes are located, the observatory said. The largest quake over the previous 24 hours was a magnitude 3.9 located under Tanaga Volcano.

No eruptive activity or signs of unrest was detected in satellite or other monitoring data.

The island is about 1,250 miles (2,012 kilometers) southwest of Anchorage. There are no communities there, but Adak, a city of about 170 people on another island, is about 65 miles (105 kilometers) away and could see ashfall.

If one of the volcanoes were to erupt, it could be a problem for aircraft. The Aleutians are below the routes that jets fly between North America and Asia. Volcanic ash is angular and sharp and can cause airplane engines to shut down. Past eruptions had both ash clouds and viscous lava that moves slowly, much like what happened at Mount St. Helens in Washington state in 1980.

No historical eruptions are known from Takawangha but field work shows recent eruptions have occurred and its possible historic eruptions attributed to Tanaga may instead have come from Takawangha, according to scientists.

The last eruption from Tanaga Volcano was in 1914.



Jungle Music: Chimp Drumming Reveals Building Blocks of Human Rhythm

In this photo provided by researchers, a wild male chimpanzee produces a pant-hoot call to elicit a response from distant group members and reunite with them in the Budongo Forest of Uganda in June 2016. (Adrian Soldati via AP)
In this photo provided by researchers, a wild male chimpanzee produces a pant-hoot call to elicit a response from distant group members and reunite with them in the Budongo Forest of Uganda in June 2016. (Adrian Soldati via AP)
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Jungle Music: Chimp Drumming Reveals Building Blocks of Human Rhythm

In this photo provided by researchers, a wild male chimpanzee produces a pant-hoot call to elicit a response from distant group members and reunite with them in the Budongo Forest of Uganda in June 2016. (Adrian Soldati via AP)
In this photo provided by researchers, a wild male chimpanzee produces a pant-hoot call to elicit a response from distant group members and reunite with them in the Budongo Forest of Uganda in June 2016. (Adrian Soldati via AP)

Like humans, chimpanzees drum with distinct rhythms - and two subspecies living on opposite sides of Africa have their own signature styles, according to a study published in Current Biology.

Previous work showed chimpanzees pound the huge flared buttress roots of rainforest trees to broadcast low‑frequency booms through dense foliage.

The idea that ape drumming might hold clues to the origins of human musicality has long fascinated scientists, but collecting enough clean data amid the cacophony of the jungle had, until now, proven elusive.

“Finally we've been able to quantify that chimps drum rhythmically - they don't just randomly drum,” lead author Vesta Eleuteri of the University of Vienna told AFP.

The findings lend fresh weight to the theory that the raw ingredients of human music were present before our evolutionary split from chimpanzees six million years ago.

For the new study, Eleuteri and colleagues - including senior authors Catherine Hobaiter of the University of St Andrews in the UK and Andrea Ravignani of Sapienza University in Rome - compiled more than a century's worth of observational data.

After cutting through the noise, the team focused on 371 high-quality drumming bouts recorded from 11 chimpanzee communities across six populations living in both rainforest and savannah-woodland habitats across eastern and western Africa.

Their analysis showed that chimpanzees drum with definitive rhythmic intent - the timing of their strikes is not random.

Distinct differences also emerged between subspecies: western chimpanzees tended to produce more evenly timed beats, while eastern chimpanzees more frequently alternated between shorter and longer intervals.

Western chimps also drummed more frequently, kept a quicker tempo, and began drumming earlier in their signature chimp calls, made up of rapid pants and hoots.

The researchers do not yet know what is driving the differences - but they propose that it might signify differences in social dynamics.

The western chimps' faster, predictable pulse might promote or be evidence of greater social cohesion, the authors argue, noting that western groups are generally less aggressive toward outsiders.

By contrast, the eastern apes' variable rhythms could carry extra nuance - handy for locating or signaling companions when their parties are more widely dispersed.

Next, Hobaiter says she would like to study the data further to understand whether there are intergenerational differences between rhythms within the same groups.

“Music is not only a difference between different musical styles, but a musical style like rock or jazz, is itself going to evolve over time,” she said.

“We're actually going to have to find a way to tease apart group and intergenerational differences to get at that question of whether or not it is socially learned,” she said. “Do you have one guy that comes in with a new style and the next generation picks it up?”