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ABSTRACTEcosourcing seed of ‘local genetic stock’ for ecological restoration has been practiced in New Zealand for about 50 years. However, we believe that it has become unnecessarily restrictive. Ecosourcing ensures plants used for restoration are adapted to local conditions and maintains current distributional patterns. It also restricts genetic diversity, confines species to their historic range, and reduces the conservation options for threatened species. For example, New Zealand tree species, the life form most frequently used in restoration plantings, have low population genetic differentiation and high net migration of alleles throughout their range. Therefore, very little is gained through restrictive ecosourcing of tree seed. Furthermore, avoidance of the danger of inbreeding depression and widening the scope for closer environmental matching, argues for larger rather smaller source areas. Climate change, extinctions across multiple trophic levels, habitat loss and fragmentation, spread of invasive species, and novel habitats have completely altered the contemporary biotic landscape. Conservation needs to engage with these changes if it is to protect and restore ecosystems. Restrictive ecosourcing is counter-productive as it limits utilising genotypic, phenotypic and ecotypic diversity, and thus the evolutionary potential of indigenous species and ecosystems. It also reduces opportunities to protect biodiversity when populations are small, and limits response to climate change. A new approach is needed. We recommend that phylogeographic patterns and biogeographic boundaries be used to set nine broad ecosourcing regions and, within these regions, phenotypic adaptation to particular environments be used as a guide to seed selection. This more relaxed approach to ecosourcing will improve restoration outcomes through increasing species and genetic diversity, reducing the detrimental effects of inbreeding and promoting the genetic rescue of populations of threatened species. Examples of adopting an eco-evolutionary approach to ecosourcing are provided for the early-successional coloniser Kunzea ericoidesand late-successional conifer species.

ABSTRACTIn vascular plant systematics there are sometimes conflicts between phenotypic and ecotypic variation and genetic differentiation that challenge species concepts, introduce taxonomic confusion, and create nomenclatural uncertainty. Until a 2014 taxonomic revision that segregated Kunzea ericoidesinto 10 species, it and K. sinclairiiwere the only species recognised in New Zealand. A recent DNA microsatellite study failed to support any of the new species, instead revealing biogeographic variation. Here we present the results of a genotyping by sequencing study with 1,361 single nucleotide polymorphisms (SNPs), sampling 48 populations representing four Kunzeaspecies from South Island and southern North Island. The SNP study confirms the microsatellite findings: the two widespread species, K. robustaand K. serotina, are indistinguishable and share northern and southern genotypes with other species; a single metapopulation lineage reflects a national north-to-south clinal pattern; and population differentiation is low and net migration high. A significant isolation by distance pattern was revealed with SNPs. The 2014 revision was explicitly based on the unified species concept, but the primary criterion, that each species represents a separate metapopulation lineage, was not demonstrated. Species recognition was based on morphological and ecological criteria that have proved difficult to apply. Applying the unified species concept and the primary criterion of a single metapopulation genetic lineage, we now recognise just a single New Zealand species, K. ericoides, with other species constituting taxonomic synonyms. In doing so, we distinguish a grey zone of taxonomic uncertainty that reflects incomplete lineage sorting, gene flow coupled with a lack of reproductive isolation, and only partial ecotypic and phenotypic differentiation. As demonstrated in the Kunzearevision, there is considerable phenotypic and ecotypic variation in regional populations that is likely to be of ecological and conservation importance. We suggest informal ecotypes are a better way to recognise this level of variation.

ABSTRACTLineage through time plots (LTTs) are often used to explore past patterns of lineage diversification and community assembly. However, as they are based solely on extant species their ability to accurately depict past events can be questioned. Here, simulation models based on neutral processes are used to explore immigration and extinction scenarios to assist with interpretation of LTT plots generated from molecular clock age estimates for a nearly complete set of extant New Zealand vascular plant genera. With significant genus turnover, model simulations yield smooth exponential and linear semi-log LTT plots. Abrupt changes in extinction and immigration rates imposed in the scenarios caused only slight alterations of the curves. The vast majority of New Zealand vascular plant genera derive from trans-oceanic dispersal, and LTT plots generated from divergence dates and fossil data indicate consistently high turnover. Even major geological and climatic events leave minor signatures on LTT plots. Most notably, the maximum Oligocene Marine Transgression (27–22 Ma), when at least 85% of the current landmass was inundated, isn’t clearly registered. By themselves, LTT plots shed little light on the biotic effects of climatic or geomorphic change in the remote past and need to be interpreted in the light of fossil and geological data.

This protocol describes how to sequence the transcriptome from a single nucleus. It is particularly suited to cell types that are difficult to isolate as intact whole cells, such as neurons.

Verification of the Visible Infrared Imager Radiometer Suite (VIIRS) End-to-End (E2E) sensor calibration is highly recommended before launch, to identify any anomalies and to improve our understanding of the sensor onorbit calibration performance. E2E testing of the Reflective Solar Bands (RSB) calibration cycle was performed pre-launch for the VIIRS Flight 1 (F1) sensor at the Ball Aerospace facility in Boulder CO in March 2010. VIIRS reflective band calibration cycle is very similar to heritage sensor MODIS in that solar illumination, via a diffuser, is used to correct for temporal variations in the instrument responsivity. Monochromatic light from the NIST T-SIRCUS (Traveling Spectral Irradiance and Radiance Responsivity Calibrations using Uniform Sources) was used to illuminate both the Earth View (EV), via an integrating sphere, and the Solar Diffuser (SD) view, through a collimator. The collimator illumination was cycled through a series of angles intended to simulate the range of possible angles for which solar radiation will be incident on the solar attenuation screen on-orbit. Ideally, the measured instrument responsivity (defined here as the ratio of the detector response to the at-sensor radiance) should be the same whether the EV or SD view is illuminated. The ratio of the measured responsivities was determined at each collimator angle and wavelength. In addition, the Solar Diffuser Stability Monitor (SDSM), a ratioing radiometer designed to track the temporal variation in the SD Bidirectional Reflectance Factor (BRF) by direct comparison to solar radiation, was illuminated by the collimator. The measured SDSM ratio was compared to the predicted ratio. An uncertainty analysis was also performed on both the SD and SDSM calibrations.

We have determined the projected rotational velocities of 13 blue horizontal-branch (BHB) stars in the globular cluster M13 via rotational broadening of metal absorption lines. Our sample spans the photometric gap observed in the horizontal-branch distribution at Teff [?] 11,000 K and reveals a pronounced difference in stellar rotation on either side of this feature--blueward of the gap, all the stars show modest rotations, v sin i < 10 km s-1, while to the red side of the gap, we confirm the more rapidly rotating population (v sin i [?] 40 km s-1) previously observed by R. C. Peterson and coworkers. Taken together with these prior results, our measurements indicate that a star's rotation is indeed related to its location along the HB, although the mechanism behind this correlation remains unknown. We explore possible connections between stellar rotation and mass-loss mechanisms which influence the photometric morphology of globular cluster HBs.

A detailed model atmosphere and chemical composition analysis has been made of the brightest known anomalous Cepheid, V19 in the globular cluster NGC 5466. Our study is based on 30 minute CCD echelle spectrograms (4300 [?] l [?] 6630 A) acquired in 1995 and 1996 with the HIRES spectrograph on the 10 m Keck-I telescope. New CCD photometric observations from 1992 to 1996 suggest that V19 was near minimum light at the time each spectrum was acquired, a conclusion that is also supported by spectral analyses using Kurucz model atmospheres. The line widths in the HIRES spectra are quite narrow, with v sin i [?] 18 km s-1. Given that V19 is the first anomalous Cepheid (AC) to be observed at such high spectroscopic resolution, the rotational velocity is significant in view of the hypothesis that ACs are coalesced binaries. The upper limit on v sin i for V19 appears to contradict this hypothesis, unless sin i is very small. Radial velocities derived from each HIRES spectrogram, vr = +111.0 +- 0.1 km s-1 in 1995 August and vr = +110.9 +- 0.2 km s-1 in 1996 June, are smaller than would be expected at minimum light based on previous, though much less precise, radial velocity measurements. The lack of a detectable change in vr over 311 days, if reinforced by continued monitoring, would also call into question the evolutionary scenario that explains V19 as the result of mass transfer in a close binary system presently composed of an AC plus a white dwarf, unless the orbit is in the plane of the sky. The atmospheric parameters of V19 at the time of the 1995 HIRES observation (ph = 0.51 +- 0.03) are estimated to have been Teff = 6450 +- 50 K, log g = 2.55 +- 0.15 dex, and microturbulence x = 2.5 +- 0.2 km s-1, in agreement with photometric light-cycle measurements near minimum light. The spectroscopic estimates are based on theoretical line profile fits to the observed wings of the H I Balmer lines Hg, Hb, and Ha, together with an investigation of the ionization equilibria of Fe I:Fe II and Mg I:Mg II, taking into account the effects of non-LTE. Adopting these atmospheric parameters and a distance modulus for NGC 5466 of (m - M)0 = 16.01 +- 0.10 gives a spectroscopic mass estimate for V19 of 1.66 + 0.7[?]0.5 _{{\odot}} $_{&sun;}$ , which is significantly larger than the mass of the main-sequence turnoff stars in NGC 5466. Equivalent width measurements of 26 Fe II lines give an iron abundance of [Fe/H] = -1.92 +- 0.05 dex. This value is consistent with previous determinations of the mean metallicity for NGC 5466 from integrated spectra and from lower S/N echelle spectroscopy of individual red giant stars, to within the quoted uncertainties. The absence of the strongest lines of Zn I suggests a possible underabundance of this element. No evidence is found for strong s-process enrichment, with [Ba/H] = -2.45 +- 0.13 dex from four Ba II lines, consistent with our upper limits [La/H] [?] -1.93, [Ce/H] [?] -1.69, and [Nd/H] [?] -1.75, based on the marginal detections or absences of the strongest La II, Ce II, and Nd II lines in the spectral regions recorded. Calcium is enhanced with respect to iron, with [Ca/Fe] = +0.22 dex derived from 16 Ca I lines and 56 Fe I lines, under the assumption of LTE; other a-elements (e.g., Mg, Si, S, and Ti) are also enhanced relative to iron. In general, the abundance ratios to iron closely match the normal, well-established pattern for metal-poor stars. This result further constrains evolutionary models attempting to explain anomalous Cepheid stars like V19 as the result of coalescence or mass transfer in an evolved binary system; unlike the velocity evidence, this abundance constraint applies regardless of inclination. Finally, the rate of change of V19's pulsation period was investigated using photometry of new CCD frames taken in 1995 and 1996 with the Dominion Astrophysical Observatory 1.8 m telescope and taken in 1996 with the Hale 5 m telescope at Palomar Observatory. This new photometry was combined with unpublished 1992 and 1993 data (courtesy of M. Corwin) and all earlier photometry available from the literature. If the period is assumed to be constant, then the new O-C diagram suggests a revised period of P = 0d.821307. However, if the O-C data are fitted allowing P to change linearly with time, then the derived period change rate, b = dP/dt = -0d.28 +- 0d.19 Myr-1, would imply that V19 is evolving toward hotter temperature, and its pulsation period at the present epoch (1996; JD = 2,450,250) is instead P = 0d.8213010 +- 0d.0000003. In either case, the residuals in the O-C diagram suggest a possible long-term (Porb ~ 10,000 day) binary motion. Any such companion would be far too distant to have contributed to the mass of V19 through Roche lobe overflow.

We describe the design, construction, and performance of an efficient new flexure-compensated Cassegrain echelle spectrograph for the 2.1 m (82-inch) Struve reflector at McDonald Observatory. The instrument has a resolving power R = lambda/Delta-lambda of 60,000 for two CCD pixels (for a reciprocal velocity dispersion of 2.5 km s-1per pixel) and provides continuous wavelength coverage for lambda < 8000 A using a thinned backside illuminated Reticon 1200 X 400 CCD detector. Total wavelength coverage in a single exposure varies from roughly 500 A at lambda = 4400 A (range 4200 - 4700 A) to 2500 A at lambda = 7500 A (range 6500 - 9000 A), and the total system efficiency at lambda = 6000 A from the top of the atmosphere through the telescope, spectrograph, and CCD detector is 10 percent or more. The mechanical design of the Cassegrain-mounted spectrograph incorporates a unique cantilevered counterweight system designed to drastically reduce the effects of gravitational flexure. In spite of the large physical size of the Cassegrain instrument, worst case flexure shifts over 60-degrees (4 hours) of telescope motion are less than 1/2-pixel and are typically on the order of 0.2 pixels or less from all sources. A subsequent paper will describe the CCD and associated electronics in detail.

High-quality Keck HIRES echelle spectra of two A-supergiants in M31, designated 41-3654 (spectral type A2 Ia-O) and 41-3712 (A3 Ia-O), at 10.2 kpc galactocentric distance are analyzed by means of NLTE unified model atmospheres to determine the properties of their stellar winds, in particular the wind momenta. We obtain mass-loss rates of 1.9 x 10-6 and 1.1 x 10-6 M yr-1 for 41-3654 and 41-3712, respectively, with an accuracy of 15% from the fit of the Ha profiles. The terminal velocities are 200 +- 25 km s-1. In addition, the exponents of the wind velocity fields are determined (b = 2 and 3, respectively) and microturbulent velocities of the order of 20 km s-1 are found. The wind momenta of the two targets are in excellent agreement with the wind momentum-luminosity relation (WLR) for galactic A- and B-supergiants. We discuss the potential of the WLR for extragalactic distance determinations and conclude that it may allow independent distance moduli to be obtained with an accuracy of 10%.