Monday, September 28, 2015
Ancient insects, lost in time, in Kaua`i's amazing Makauahi Cave
Deep in the sediments of Kaua`i’s Makauahi sinkhole is
evidence of an entire collection of insects, lost in time and now extinct.
They represent some of the diverse life forms of the
Hawaiian lowland forest that once spilled from the foothills of Ha`upu
mountain.
The beetles are in the genus Blackburnia, and help fill in missing pieces in the evolution of the Islands, according to anarticle in the journal Invertebrate Systematics, by James K. Liebherr and Nick
Porch, of Cornell University and Australia’s Deakin University, respectively.
“The addition of
extinct Kauai species to clades previously known only from extant species on
Maui Nui and Hawaii Island reinforces the biogeographic pattern of progressive colonization
by Blackburnia beetles from older Hawaiian islands to younger,” they write.
The paper is entitled “Reassembling a lost lowland carabid beetle assemblage (Coleoptera)
from Kauai, Hawaiian Islands.”
The new findings link known species of beetles from ancient Laysan
Island to young Hawai`i Island.
Scientists had some fun with naming the new species. They
are Blackburnia burneyi, B. cryptipes, B.
godzilla, B. menehune, B. mothra, B. ovata and B. rugosa.
Several of the newly named species are significantly larger
than any of the living relatives on Kauai, which explains their names. B. godzilla is the biggest of all, and mothra is another big one.
The first, B. burneyi, is named for David A. Burney,
who led the excavation of the famous south Kaua`i limestone feature known as
Makauahi. His wife and partner, Lida Pigott Burney helps manage the cave
reserve.
For more information on the amazing sinkhole and associated caves, and
the program to re-establish many of the native plant species that once existed
on this landscape, see http://cavereserve.org/. (If you like what they'd doing, please consider sending a donation.)
The beetles are believed to have gone extinct largely because
of human-caused destruction of their habitat. The beetle parts were found in
sediments dated to before the arrival of Polynesians in the Islands, and they
disappear from sediments soon after.
“Seven of the species discovered in these deposits are not
known from any
historically collected specimens,
supporting the conclusion that these species suffered extinction through
the agencies of Polynesian agricultural land conversion and introduction of
invasive predators such as the Pacific rat,” the paper says.
The authors of the paper don’t believe they have yet
collected enough material to be able to describe all of the insects of this
prehistoric South Kaua`i habitat, but there’s a suggestion more may be learned.
“We do not claim to have an accurate representation of the lowland
carabid fauna of Kauai that was destroyed through the agencies of man. But now
that there are fossils, there are some interesting tales to tell,” they write. Carabids are part of a global family of fast-moving ground beetles.
© Jan TenBruggencate 2015
Posted by Jan T at 12:10 PM 0 comments
Labels: Agriculture, Archaeology, Botany, Conservation, Geology, Zoology
Sunday, September 27, 2015
Battery technology exploding, in a good way
If the future of energy is
the ability to cheaply and safely store intermittent renewables, then there’s
lots of good news on the battery front.
Renewable plus storage means
decarbonizing the grid. Public policy argues that’s something we should do
effectively and as quickly as possible.
One of the problems is that
batteries haven’t been up to the task. Some are too expensive, some are too
toxic, some are too fragile, some lose too much energy charging and
discharging, some die too soon and need to be replaced.
The list goes on.
But there’s amazing work being done globally on battery technology. We have reviewed some of that in an
earlier series that starts here.
But since that 2013 series,
there’s lots of new stuff. We’ll review a couple of innovations here, starting with flow batteries. .
Researchers at Harvard have
been looking for non-toxic alternatives to flow batteries using bromide
electrolytes. Flow batteries have energy-rich electrolytes in external tanks, and the electrolytes are pumped through the battery, meaning battery
capacity can be increased simply by increasing electrolyte storage.
“Harvard chemistry professor Roy
Gordon said they found a formulation using cheap, common materials that “deliver
the first high-performance, non-flammable, non-toxic, non-corrosive and
low-cost chemicals for flow batteries. They reported their research in the Sept. 25
issue of Science.
Project chief investigator
Michael Aziz said it would be a great way to store solar power: “"This is
chemistry I'd be happy to put in my basement. The non-toxicity and cheap,
abundant materials placed in water solution mean that it's safe -- it can't
catch on fire -- and that's huge when you're storing large amounts of
electrical energy anywhere near people."
Scientists at Ohio State have
combined a solar cell and a battery in what they’re calling an aqueous solar
flow battery. It’s still a ways from commercial production, but its inventors
believe it has a lot of potential.
"This solar flow battery
design can potentially be applied for grid-scale solar energy conversion and
storage, as well as producing 'electrolyte fuels' that might be used to power
future electric vehicles," said lead author Mingzhe Yu. They reported their findings in the Journal of the American Chemical Society.
Stanford researchers have
written about their new aluminum battery, which they say is fast-charging,
inexpensive and lasts a long time. They believe it can replace alkaline and
lithium-ion batteries. How fast a charge? Think about charging a cell phone in
a minute, and a battery that can handle daily charging for decades.
The battery has an aluminum
anode and graphite cathode in a liquid salt electrolyte. It still needs some
work, but shows great potential, its inventors say.
And it’s not just for small
electronics. “The grid needs a battery with a long cycle life that can rapidly
store and release energy. Our latest unpublished data suggest that an aluminum
battery can be recharged tens of thousands of times,” said Stanford chemistry
professor Hongjie Dai.
But this isn’t to say that
all the research is on new battery technologies. There’s also still a lot of
work underway on improving existing batteries. As an example, South Korean researchers are reporting on a new lithium-ion design that improves its
performance while reducing the problem of overheating.
And MIT researchers say they’ve
developed a way to cut in half the cost of building lithium-ion batteries.
That, and they work better, too.
Furthermore, there’s research
underway in figuring out how to improve the amount of energy lost in charging
and discharging a battery. Generally, you can lose 20 percent or more of the energy
it takes to charge a battery when to draw that energy back out.
Researchers at Case Western
Reserve University say they’ve adapted solar cells to dramatically increase that
efficiency. They wired four perovskite solar cells in series and were able to
charge a lithium-ion battery with 7.8 percent loss—the best performance seen to
date, they say.
Here is the paper, but it’s a
little technical. The Science Daily report on the work is here.
Perovskite solar cells are
comparatively new on the solar scene. They can be manufactured inexpensively,
and reportedly can convert into electricity a larger proportion of the sun’s
light than other solar panels.
A lot of folks have wondered
whether supercapacitors can be adapted to provide long-term energy storage.
Supercapacitors are units that can store a lot of power, but they discharge
almost instantaneously. Great for a sudden need for power—like when a motor
starts up—but less useful as a continuing source of energy.
But there are a lot of
applications for bursts of energy that are inefficiently met with standard
batteries. Researchers at Department of Energy's Oak Ridge National Laboratory
and Drexel University looked at new ways to use water materials—specifically old
tires—in the manufacture of supercapacitors.
The point here has not been
to cover the universe of battery innovation, but to show that there’s a lot
going on. Some of this stuff may not pan out, but a lot of it will, and it will
change the energy landscape.
Some of these technologies may end up in our phones, in our cars, in our houses, out on our utility grids--and maybe even in places where we've never imagined a role for energy storage.
© Jan TenBruggencate 2015
Posted by Jan T at 10:46 AM 3 comments
Labels: Efficient transportation, Energy, Photovoltaic, Physics, Pollution, Recycling, Solar
Monday, September 21, 2015
Butterflies, wasps and interspecies gene transfer
The more we look, the more we
find that transgenic behavior—moving genetic material between unrelated life forms,
is common in nature.
One of the hallmarks of the anti-GMO movement seems to be the argument that it’s
unnatural to move, for example, bacterial DNA into plants to make them
resistant to certain bug predators.
It not only isn’t unnatural,
but it happens all the time in nature.
“Breaching the species barrier,”
it’s called. It turns out this barrier is pretty porous.
We’ve reported earlier about
naturally transgenic sweet potatoes.
And we’ve reported on virus DNA
movement into human DNA and bacteria DNA into animals.
New evidence released just
last week shows that parasitic wasps have inserted viral DNA into butterfly
genomes. The viral DNA turns off portions of the butterfly immune system.
All of this interspecies trade allows the wasps to insert their eggs into the butterfly caterpillar phase without their being attacked by the butterfly immune systems. Creepy, but that's nature.
All of this interspecies trade allows the wasps to insert their eggs into the butterfly caterpillar phase without their being attacked by the butterfly immune systems. Creepy, but that's nature.
Here is the Sept. 17, 2015,paper
reporting on that finding. It's in the latest PLOS Genetics and is
problematically entitled "Recurrent Domestication by Lepidoptera of
Genes from Their Parasites Mediated by Bracoviruses."
The process of moving genetic
material between species is called horizontal gene transfer.
The new paper concludes that
while science has assumed that species have needed to reshuffle their own genes
to fight off new threats, in fact, horizontal gene transfer is “recognized as an
important factor in…evolution.”
“We show here that in several lineages,
lepidopteran genomes have acquired genes from a bracovirus that is
symbiotically used by parasitic wasps to inhibit caterpillar host immune
defences,” the paper says.
The research suggests that
the wasps initially collected the viral DNA, carried it within their bodies,
and then transferred it to the butterflies. They used the viral DNA as a kind
of tool kit to allow them to carry out their own life cycles.
And there’s more. It appears
that the butterflies have then been able to use the borrowed genes to fight off
a virus that can attack them.
“Additionally, we present
functional analyses suggesting that some of the acquired genes confer to
caterpillars a protection toward baculovirus, a very common pathogen in the
field. This phenomenon may have implications for understanding how caterpillars
acquire resistance against baculoviruses used in biological control,” the paper
says.
Evolutionary biologist Louise
Johnson, at the British University of Reading, said it’s a fine example of just
how adaptive evolution can be.
"This three-way gene shuffle
is a particularly clear and clever example: wasps use viruses to attack
butterflies, but those viruses have also allowed the butterflies to steal genes
from the wasps.
“It’s clear that the stolen
genes are useful to the butterflies, so naturally occurring genetic engineering
helps them to survive.
“From my perspective as an
evolutionary biologist, it’s also a perfect illustration of how evolution uses
every trick in the book, and the book is bigger than we think,” Johnson said.
© Jan TenBruggencate 2015
Posted by Jan T at 9:26 AM 1 comments
Labels: Agriculture, Botany, Genetic engineering, Health/Medical, technology, Zoology
Wednesday, September 2, 2015
Sea level rise has been artificially low in Hawai`i—but it’s going to catch up
Sea levels are rising globally at an increasing rate—three inches
in the last 25 years or so--but we’re not seeing that much in Hawai`i.
So what’s up?
One answer to this mystery is that our islands are in a kind
of temporary sweet spot. Satellite imagery shows that while most of the globe
has seen dramatic rises in sea levels—as much as 3 inches in the past 25 years—Hawai`i
has been flat to actually lower.
(Image: The red shows areas of dramatic sea level rise. Blue
shows areas where it’s flat or down. Hawai`i appears in the blue zone. But how
long will that last? Credit: NASA.)
At a human scale, this makes no sense. If you fill a
bathtub, clearly it fills all around the tub.
But global scales are different. There are humps and valleys
in the oceans across the scale of thousands of miles. Winds can push water up
against a coast, creating a hump. Eddies can change sea levels regionally.
Currents and storms and tides and even temperatures can all impact the height
of the ocean.
“In a nutshell it's due to changes in winds and ocean
circulation that counteract the global sea level signal regionally. That should shift as part of a long-term
fluctuation but no projections on when that is likely to occur. This big El Nino may herald the start of a
shift, but we have to see how that plays out,” said University of Hawai`i
oceanographer Mark Merrifield.
Here is NASA’s recent report on accelerating sea levels and related
issues.
“Sea levels are rising rapidly—much more rapidly than they
have any time in the last several thousand years,” said NASA’s Joshua Willis,
at the Jet Propulsion Laboratory.
And the rate of increase has been increasing as well, he
said. It was about 1 millimeter annually in 1900, rose to 2 millimeters
annually in the mid 1900s, and is now at 3 millimeters annually. That works out
to more than an inch a decade.
I wrote to Willis to ask whether our islands can continue to
dodge this bullet.
“In the long run sea level rise will affect Hawaii as well. Because
it is in the central Pacific, the impacts of the long-term natural cycles may
not be quite as large. Eventually, however, the global rates of rise will be
felt in Hawaii also,” he said.
University of Hawai`i coastal geologist Charles “Chip”
Fletcher agreed.
“The global oceans cannot keep rising without us
experiencing the rise as well - we just may be able to avoid the worst aspects
of the variability. On the other hand, models show that the tropics as a region
will experience the upper end of global sea level change, so that makes us part
of a more dangerous region.
“I have held for several years that Hawaii should plan for one
meter of sea level rise by end of century and as far as I can see that is still
a valid number,” he said.
© Jan TenBruggencate 2015
Posted by Jan T at 1:28 PM 4 comments
Labels: Climate Change, Geology, Marine Issues, Oceanography, Reefs, Weather, Wind
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