1,324 research outputs found
The Complementarity of Redshift-space Distortions and the Integrated Sachs-Wolfe Effect: A 3D Spherical Analysis
Assuming General Relativity is correct on large-scales, Redshift-Space
Distortions (RSDs) and the Integrated Sachs-Wolfe effect (ISW) are both
sensitive to the time derivative of the linear growth function. We investigate
the extent to which these probes provide complementary or redundant information
when they are combined to constrain the evolution of the linear velocity power
spectrum, often quantified by the function , where is the
logarithmic derivative of with respect to . Using a spherical
Fourier-Bessel (SFB) expansion for galaxy number counts and a spherical
harmonic expansion for the CMB anisotropy, we compute the covariance matrices
of the signals for a large galaxy redshift survey combined with a CMB survey
like Planck. The SFB basis allows accurate ISW estimates by avoiding the
plane-parallel approximation, and it retains RSD information that is otherwise
lost when projecting angular clustering onto redshift shells. It also allows
straightforward calculations of covariance with the CMB. We find that the
correlation between the ISW and RSD signals are low since the probes are
sensitive to different modes. For our default surveys, on large scales (k<0.05
\Mpc/h), the ISW can improve constraints on by more than 10%
compared to using RSDs alone. In the future, when precision RSD measurements
are available on smaller scales, the cosmological constraints from ISW
measurements will not be competitive; however, they will remain a useful
consistency test for possible systematic contamination and alternative models
of gravity.Comment: 11 pages, 7 figures, published in MNRA
Age-related changes in migratory behaviour within the first annual cycle of a passerine bird
Funding was awarded to WC from the A.P. Leventis Conservation Foundation.First time migrants (juveniles hereafter) of many species migrate without specific knowledge of non-breeding locations, but experience may aid adults in timing and route decisions because they can migrate more efficiently to their previous non-breeding sites. Consequently, we expect a transition to more efficient migratory behaviour with age, but when and how this happens is little known. We used light-level geolocator data from Cyprus wheatears Oenanthe cypriaca to compare migration timing and route directness between juveniles and adults, and repeatability of their timing and non-breeding locations. We predicted that juveniles would depart and arrive later than adults for both autumn and spring migration; that duration of migration would be greater for juveniles; that routes taken by juveniles would be less direct than those for adults; and that autumn and spring departure timing, and non-breeding locations, would be more repeatable for adults between two years than for juveniles between their first and subsequent migration. We found that juveniles departed significantly later than adults in autumn but there was no difference in arrival timing, and although spring departure timings did not differ, juveniles arrived on the breeding grounds later than adults. Nevertheless, we found no significant age-related difference in the duration of migration in autumn or spring. Yet, juvenile migrations were less direct than those of adults in autumn, but not spring. We found evidence that spring departure timing and non-breeding locations were repeatable for adults but not juveniles. Our findings show that age-related changes in migratory behaviour begin to occur during the first annual cycle demonstrating the potential for early adaptation to environmental variability within an individualâs life.Publisher PDFPeer reviewe
The potential function of post-fledging dispersal behavior in first breeding territory selection for males of a migratory bird
We thank the A.P. Leventis Conservation Foundation for supporting this work.One possible hypothesis for the function of post-fledging dispersal is to locate a suitable future breeding area. This post-fledging period may be particularly important in migratory species because they have a limited period to gather information prior to autumn migration, and in protandrous species, males must quickly acquire a territory after returning from spring migration to maximize their fitness. Here we use color-ring resightings to investigate how the post-fledging dispersal movements of the Cyprus wheatear Oenanthe cypriaca, a small migratory passerine, relate to their first breeding territory the following year when they return from migration. We found that males established first breeding territories that were significantly closer to their post-fledging location than to their natal sites or to post-fledging locations of other conspecifics, but these patterns were not apparent in females. Our findings suggest that familiarity with potential breeding sites may be important for juveniles of migratory species, particularly for the sex that acquires and advertises breeding territories. Exploratory dispersal prior to a migrantâs first autumn migration may contribute toward its breeding success the following year, further highlighting the importance of early seasonal breeding on fitness and population dynamics more generally.Publisher PDFPeer reviewe
Source of Variant Creutzfeldt-Jakob Disease outside United Kingdom
Bovine imports during the 1980s and the first half of the 1990s from the UK contributed substantially to the global spread of this disease
Female song in the Cyprus Wheatear Oenanthe cypriaca
We thank the A.P. Leventis Conservation Foundation for supporting this work.Female song is widespread across bird species yet rarely reported. Here, we report the first observations and description of female song in the Cyprus Wheatear Oenanthe cypriaca and compare it to male song through the breeding season. Twenty-five percent of colour-ringed females were observed singing at least once, predominantly in April, compared to 71% of males that continued singing through the breeding period. We suggest that female song may have multiple functions in this species, but it may be especially important in territorial defence and mate acquisition.Publisher PDFPeer reviewe
Chimpanzee Rights: The Philosophers' Brief
In December 2013, the Nonhuman Rights Project (NhRP) filed a petition for a common law writ of habeas corpus in the New York State Supreme Court on behalf of Tommy, a chimpanzee living alone in a cage in a shed in rural New York (Barlow, 2017). Under animal welfare laws, Tommyâs owners, the Laverys, were doing nothing illegal by keeping him in those conditions. Nonetheless, the NhRP argued that given the cognitive, social, and emotional capacities of chimpanzees, Tommyâs confinement constituted a profound wrong that demanded remedy by the courts. Soon thereafter, the NhRP filed habeas corpus petitions on behalf of Kiko, another chimpanzee housed alone in Niagara Falls, and Hercules and Leo, two chimpanzees held in
research facilities at Stony Brook University. Thus began the legal struggle to move these chimpanzees from captivity to a sanctuary, an effort that has led the NhRP to argue in multiple courts before multiple judges. The central point of contention has been whether Tommy, Kiko, Hercules, and Leo have legal rights. To date, no judge has been willing to issue a writ of habeas corpus on their behalf. Such a ruling would mean that these chimpanzees have rights that confinement might violate. Instead, the judges have argued that chimpanzees cannot be bearers of legal rights because they are not, and cannot be persons. In this book we argue that chimpanzees are persons because they are autonomous
1989 Texas DTPA Reform: Closing the DTPA Loophole in the 1987 Tort Reform Laws and the Ongoing Quest for Fairer DTPA Laws.
Abstract Forthcoming
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