New Scientist - USA (2021-02-06)

(Antfer) #1
Marine life

New whale species
found hiding
in plain sight

A SMALL group of whales living in
the Gulf of Mexico belong to a new
species that went unacknowledged
until now. As there are fewer than
100 of them, they are immediately
an endangered species. The new
species is a type of baleen whale,
which filter food out of the water.
Scientists already recognised
a species called Bryde’s whale
(Balaenoptera edeni), which lives
in and around the tropics. It isn’t
clear if they are actually all one
species, or several, so they are
often called Bryde’s-like whales.
There are still thought to be
two subspecies, says Patricia
Rosel at the National Oceanic

and Atmospheric Administration’s
Southeast Fisheries Science Center
in Louisiana. Since 2003, some
other Bryde’s-like whales from the
Indian Ocean have been recognised
as a species called Omura’s whale.
Rosel and her colleagues study
Bryde’s-like whales in the Gulf of

Mexico. “We kind of knew, starting
in the 1990s, that there was this
resident small population,” she says.
In 2014, the researchers
published an analysis of tissue
samples, which showed that the
whales were genetically distinct
from other Bryde’s-like whales.

“But we didn’t have a skull”, which
is crucial for identifying a new
whale species, she says.
In January 2019, the researchers
obtained a skull following a whale
stranding in Florida. It was distinct
from those of other Bryde’s-like
whales. Along with further genetic
evidence, they say this is enough to
establish the Gulf of Mexico whales
as a new species (Marine Mammal
Science, doi.org/fsf6).
They have named the species
Balaenoptera ricei. Little is known
about its behaviour, says Rosel,
although there are hints that it
dives deep to feed, unlike other
Bryde’s-like whales. ❚

6 February 2021 | New Scientist | 17

A SIMULATION that runs faster
on a commercial graphics card
than on some supercomputers
could drastically cut the cost of
studying how our brains work.
Researchers have long used
digital models to better
understand our brains in the hope
of developing cures for diseases
such as Alzheimer’s or Parkinson’s,
but simulating the number of
neurons and synapses in even
the simplest creature can be a
struggle for supercomputers.
Before running a simulation
of the brain’s neurons and vast
number of synaptic connections,
the model must be transferred
into the computer’s working
memory, complete with the
starting state of every synapse.
As the simulation progresses, the
computer must keep referring to
this set of data to retrieve or
update the state of each synaptic
connection, which acts as a

bottleneck on calculations.
Commercial graphics cards,
known as GPUs, are designed
to render 3D scenes by rapidly
carrying out many arithmetic
calculations in parallel, an ability
that also makes them particularly
speedy at other tasks, including
simulating synaptic connections.
James Knight at the University
of Sussex, UK, and his colleagues
created a simulation that uses a
random number generator as
part of the process of creating
a synaptic state. Although this
random element means the
simulation can’t refer to the exact
starting state of the model each
time it needs to create a new
connection, the team found it
produced results comparable
to conventional simulations.
It also makes things faster, as the
computer only needs to handle
data about the synapses that it
is currently modelling.

The team used an existing
model of a macaque monkey’s
visual cortex, consisting of more
than 4 million neurons, as a
benchmark. In 2018, 1 second
of brain activity inside the model
was simulated on an IBM Blue
Gene/Q supercomputer in
12 minutes. Using a commercially
available graphics card, Knight’s

team was able to carry out the task
in just under 8 minutes (Nature
Computational Science, DOI:
10.1038/s43588-020-00022-7).
A newer JURECA supercomputer
has been able to run the same
simulation in just 31 seconds,
but these can cost tens of millions
of pounds and require a team of
staff to maintain. By contrast,

Knight says the Nvidia Titan RTX
hardware used in his tests costs
just a few thousand pounds.
“This potentially means that
researchers whose primary focus
isn’t dealing with supercomputers
could explore things with this
model,” he says.
But there is a flaw. When we
learn, our brains are constantly
weakening or strengthening the
connections between synapses,
an ability known as synaptic
plasticity. The GPU simulation
can’t do this, because it always
has to recalculate the connections
from scratch, reverting back to
the model’s original state.
Knight believes a hybrid
approach using his new technique
and a traditional model where
the state of synapses is stored in
memory and can be updated would
allow plasticity where needed and
high speed where it isn’t, but the
team has yet to try this. ❚

Matthew Sparkes

NO

AA

Michael Marshall

Computing

Brain simulation on the cheap


Video game graphics cards could be used for low-cost digital models of brains


8
Minutes to simulate 1 second
of a monkey’s visual cortex

The new species of
whale has been named
Balaenoptera ricei
Free download pdf