203 research outputs found
On Neanderthal crania and speech: Response to Lieberman
This is the publisher's version, also available electronically from http://www.jstor.org/stable/274428
Ötzi the Iceman. Examining new evidence from the famous copper age mummy
The Iceman mummy, nicknamed Ötzi, was discovered in 1991 amidst sheets of melting ice on the Tisenjoch pass of the Similaun glacier in the Tyrolean Alps. He was found on the border between Italy and Austria, at an altitude of 3,200 m above sea level. He is a well-preserved male human corpse, dark in color, and dates to the early Copper Age, indicating he is more than 5,000 years old (ca. 3,250 yrs. cal BCE). His belongings, scattered around the body, included a bow and quiver with arrows, a complete copper-bladed axe, a flint dagger with a wicker sheath, two birch wood vessels clad with maple leaves, remnants of a backpack, a leather pouch with small objects, fur and leather garments, shoes, and other minor artifacts. When scientists realized the antiquity of the find, the media response was overwhelming and Ötzi captivated audiences far and wide
Molecular Gas in the z=1.2 Ultraluminous Merger GOODS J123634.53+621241.3
We report the detection of CO(2-1) emission from the z=1.2 ultraluminous
infrared galaxy (ULIRG) GOODS J123634.53+621241.3 (also known as the
sub-millimeter galaxy GN26). These observations represent the first discovery
of high-redshift CO emission using the new Combined Array for Research in
Millimeter-Wave Astronomy (CARMA). Of all high-redshift (z>1) galaxies within
the GOODS-North field, this source has the largest far-infrared (FIR) flux
observed in the Spitzer 70um and 160um bands. The CO redshift confirms the
optical identification of the source, and the bright CO(2-1) line suggests the
presence of a large molecular gas reservoir of about 7x10^10 M(sun). The
infrared-to-CO luminosity ratio of L(IR)/L'(CO) = 80+/-30 L(sun) (K Km/s
pc^2)^-1 is slightly smaller than the average ratio found in local ULIRGs and
high-redshift sub-millimeter galaxies. The short star-formation time scale of
about 70 Myr is consistent with a starburst associated with the merger event
and is much shorter than the time scales for spiral galaxies and estimates made
for high-redshift galaxies selected on the basis of their B-z and z-K colors.Comment: Accepted for publication in ApJ Letter
Hand to mouth in a Neandertal : right-handedness in regourdou 1
We describe and analyze a Neandertal postcranial skeleton and dentition, which together show unambiguous signs of right-handedness. Asymmetries between the left and right upper arm in Regourdou 1 were identified nearly 20 years ago, then confirmed by more detailed analyses of the inner bone structure for the clavicle, humerus, radius and ulna. The total pattern of all bones in the shoulder and arm reveals that Regourdou 1 was a right-hander. Confirmatory evidence comes from the mandibular incisors, which display a distinct pattern of right oblique scratches, typical of right-handed manipulations performed at the front of the mouth. Regourdou's right handedness is consistent with the strong pattern of manual lateralization in Neandertals and further confirms a modern pattern of left brain dominance, presumably signally linguistic competence. These observations along with cultural, genetic and morphological evidence indicate language competence in Neandertals and their European precursors
The Far-Infrared Luminosity Function from GOODS-N: Constraining the Evolution of Infrared Galaxies for z \leq 1
We present the IR luminosity function derived from ultra-deep 70 micron
imaging of the GOODS-North field. The 70 micron observations are longward of
the PAH and silicate features which complicate work in the MIR. We derive
far-infrared luminosities for the 143 sources with S_{70} > 2 mJy (S/N > 3
\sigma). The majority (81%) of the sources have spectroscopic redshifts, and
photometric redshifts are calculated for the remainder. The IR luminosity
function at four redshifts (z ~ 0.28, 0.48, 0.78, and 0.97) is derived and
compared to the local one. There is considerable degeneracy between luminosity
and density evolution. If the evolving luminosity function is described as
\rho(L, z) = (1 + z)^q \rho(L/(1 + z)^p, 0), we find q = -2.19p + 6.09. In the
case of pure luminosity evolution, we find a best fit of p =
2.78^{+0.34}_{-0.32}. This is consistent with the results from 24 micron and
1.4 GHz studies. Our results confirm the emerging picture of strong evolution
in LIRGs and ULIRGs at 0.4 < z < 1.1, but we find no evidence of significant
evolution in the sub-LIRG (L < 10^{11} L_{\odot}) population for z < 0.4.Comment: accepted by ApJL, 5 page
A merger in the dusty, galaxy A1689-zD1?
The gravitationally-lensed galaxy A1689-zD1 is one of the most distant
spectroscopically confirmed sources (). It is the earliest known galaxy
where the interstellar medium (ISM) has been detected; dust emission was
detected with the Atacama Large Millimetre Array (ALMA). A1689-zD1 is also
unusual among high-redshift dust emitters as it is a sub-L* galaxy and is
therefore a good prospect for the detection of gaseous ISM in a more typical
galaxy at this redshift. We observed A1689-zD1 with ALMA in bands 6 and 7 and
with the Green Bank Telescope (GBT) in band . To study the structure of
A1689-zD1, we map the mm thermal dust emission and find two spatial components
with sizes about \,kpc (lensing-corrected). The rough spatial
morphology is similar to what is observed in the near-infrared with {\it HST}
and points to a perturbed dynamical state, perhaps indicative of a major merger
or a disc in early formation. The ALMA photometry is used to constrain the
far-infrared spectral energy distribution, yielding a dust temperature (--\,K for ). We do not detect the CO(3-2) line
in the GBT data with a 95\% upper limit of 0.3\,mJy observed. We find a slight
excess emission in ALMA band~6 at 220.9\,GHz. If this excess is real, it is
likely due to emission from the [CII] 158.8\,m line at . The stringent upper limits on the [CII]/ luminosity ratio
suggest a [CII] deficit similar to several bright quasars and massive
starbursts.Comment: 9 pages, accepted to MNRAS, in pres
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