Eli Yishai's ear 58.
(photo credit: Haim Tzach)
For archeologists, finding a genuine buried site buried is often a hit-andmiss
affair. There may be a better way, says Dr. Lev Epelbaum of the geophysics and
planetary sciences department at Tel Aviv University’s Exact Sciences
The new technique, which can provide a tool to learn more about
buried cities, roads and other objects, was revealed recently by Epelbaum in the
journal Advances of Geosciences. It is based on an algorithm that unites various
bits of data while erasing “noise” (irrelevancies). Some data come from radio
transmitters of the type used to communicate with nuclear submarines, while
others use detailed magnetic field observations. As a result, decisions on how
to proceed are more easily reached.
Seven different techniques are used,
he said, so if one is neutralized, one can use any or all of the other six to
find suitable locations. For example, to locate objects dozens of meters deep,
bone densities can be compared with the densities of the environment (including
basalt and sand) in which they are found.
Existing methods for locating
sites of potential archeological and geological importance can produce
significant background “noise,” he said. This tool helps archeologists “see”
important artifacts, civilizations and objects and sort them out in a
It’s a challenge, as the surface is not smooth,
and irrelevant underground objects can cause much “noise.” Magnetic fields
change with time, so variations complicate things, said Epelbaum.
with TAU scientists Dr. Leonid Alperovitz and Dr. Valery Zaldev, Epelbaum
succeeded in reducing such “noise.” There are so many still-undiscovered objects
in Israel that his techniques will be very practical, he said. He called his
technology Multi-PAM, in which PAM stands for physical archeological
If a pilotless plane is flown a few meters over the surface to
survey broad strips of land, that alone would provide important historic and
archeological data. He estimates that there are over 20,000 undiscovered
archeological sites in this country. While the tool is aimed at improving
archeological investigations in the Fertile Crescent, Epelbaum suggests it could
also help examine more recent sites, such as old Indian burial grounds in the
NOISY AS A MOUSE
What happened to being “quiet as a mouse”?
Researchers have recently shown that, rather than being silent creatures, mice
emit ultrasonic calls in a variety of social contexts like those of bats, and
these calls have song-like characteristics.
So if mice sing, are they
born with the songs fully formed in their heads, or do they learn them from
peers? This question is of great interest to scientists as, while many organisms
produce regulated vocalizations, only a few species (such as humans) can
actually learn these vocalizations. If it turns out that mice can indeed learn
new songs, it would provide a convenient mammalian model of vocal learning.
Whether or not mouse song involves learning – either through auditory imitation
or behavioral feedback such as from the mother, however – is a subject of hot
debate. To highlight the difficulties, two studies published recently in the
open-access journal PLoS ONE have come to differing conclusions about whether
mouse vocalization patterns are innate or learned.
In the first study,
researchers from America’s Northeastern Ohio Universities Colleges of Medicine
and Pharmacy and the MRC Institute of Hearing Research conducted a study to
understand developmental changes in mouse song that would allow rodent parents
to distinguish older mice from younger mice.
They found that many
features changed with age. For example, the pattern of syllables became more
According to lead author Jasmine Grimsley, “We concluded that
the increased complexity of song suggests that mice may are capable of vocal
learning, but we also recognized that other factors besides learning, such as
genetically controlled neuromuscular development, might explain the increased
We conducted our study in normal hearing, CBA/CaJ mice, and we
intend to use the results to understand how the brain codes the meaning of these
The second study, a collaboration among Azabu University, the
RIKEN Brain Science Institute and the Okanoya Emotional Information Project in
Japan, used an experiment to test whether the vocalization patterns were more
strongly influenced by genetics or environment.
The researchers used
males from two mouse strains that emit different vocalizations. Males from each
strain were raised in litters of the opposite strain until weaning. Vocalization
patterns were recorded at 10 to 20 weeks of age, and the researchers compared
vocalizations of cross-fostered mice to control mice reared by genetic
Which is it – nature or nurture? It appears too early to say for
sure, and we don’t yet know whether the mating songs of mice, for example, are
genetically determined or learned from their parents, the researchers concluded.
What is certain, however, is that even careful scientific research does not
always produce straightforward answers.