19 research outputs found
Cowbane, Oxypolis occidentalis, A New Native Vascular Plant Species for the Queen Charlotte Islands, British Columbia
We report the recent discovery of Oxypolis occidentalis, a species that is new to both British Columbia and Canada, disjunct on the Queen Charlotte Islands
A Taxonomic Revision of the Endemic Hawaiian Lysimachia (Primulaceae) Including Three New Species
A taxonomic revision of the endemic Lysimachia of the Hawaiian
Islands was undertaken with the goal of clarifying species boundaries, especially
within the L. hillebrandii/L. remyi complex of the previous taxonomic treatment.
The endemic species appear to be monophyletic with Malesian affinities. The revision
presented here is based upon observations of morphological characters. Sixteen
species are recognized, of which three are probably extinct. Most species have
narrow ecological preferences and are endemic to a single island. Species differ
from each other most notably in the size, shape, and venation of the leaves; the
size, shape, and pigmentation of the calyx and corolla lobes; and the presence or
absence of viscid stems and leaves. Populations previously classified within L.
hillebrandii or L. remyi differ in a number of characters not previously evaluated
including vestiture, leaf color and venation, pedicel position and color, and calyx
shape and color. Three new species, L. iniki, L. pendens, and L. scopulensis, are
described. A key to species, species descriptions, and distribution maps are provided
Alpine Plant Range Extensions for Northern British Columbia, Including Two Species New to the Province
Between 2002 and 2011, we collected vascular plants from alpine areas of northern British Columbia (B.C.). We have found one species that has not previously been collected in the province: Phippsia algida. Collections of an additional three species represent significant range extensions of species already known to occur in the province: Aphragmus eschscholtzianus, Papaver alboroseum, and Montia bostockii. Our collections of Delphinium brachycentrum initially appeared to be the first records for the province; however, examination of herbarium specimens at the Royal British Columbia Museum herbarium indicated that this species had been collected prior to our field work but had been misidentified. We indicate the distribution of this species in B.C. for the first time, and we present a corrected distribution map for Tephroseris yukonensis that includes our own collections
Insect Brains Use Image Interpolation Mechanisms to Recognise Rotated Objects
Recognising complex three-dimensional objects presents significant challenges to visual systems when these objects are rotated in depth. The image processing requirements for reliable individual recognition under these circumstances are computationally intensive since local features and their spatial relationships may significantly change as an object is rotated in the horizontal plane. Visual experience is known to be important in primate brains learning to recognise rotated objects, but currently it is unknown how animals with comparatively simple brains deal with the problem of reliably recognising objects when seen from different viewpoints. We show that the miniature brain of honeybees initially demonstrate a low tolerance for novel views of complex shapes (e.g. human faces), but can learn to recognise novel views of stimuli by interpolating between or ‘averaging’ views they have experienced. The finding that visual experience is also important for bees has important implications for understanding how three dimensional biologically relevant objects like flowers are recognised in complex environments, and for how machine vision might be taught to solve related visual problems
The Molecular Identification of Organic Compounds in the Atmosphere: State of the Art and Challenges
Cowbane, <em>Oxypolis occidentalis</em>, A New Native Vascular Plant Species for the Queen Charlotte Islands, British Columbia
We report the recent discovery of Oxypolis occidentalis, a species that is new to both British Columbia and Canada, disjunct on the Queen Charlotte Islands
CALAMAGROSTIS TACOMENSIS (POACEAE): A NEW SPECIES FROM WASHINGTON AND OREGON
Volume: 53Start Page: 288End Page: 29
Morphological Analysis and Phytogeography of Native Calamagrostis (Poaceae) from British Columbia, Canada and Adjacent Regions
Volume: 58Start Page: 214End Page: 23
Alpine Plant Range Extensions for Northern British Columbia, Including Two Species New to the Province
Between 2002 and 2011, we collected vascular plants from alpine areas of northern British Columbia (B.C.). We have found one species that has not previously been collected in the province: Phippsia algida. Collections of an additional three species represent significant range extensions of species already known to occur in the province: Aphragmus eschscholtzianus, Papaver alboroseum, and Montia bostockii. Our collections of Delphinium brachycentrum initially appeared to be the first records for the province; however, examination of herbarium specimens at the Royal British Columbia Museum herbarium indicated that this species had been collected prior to our field work but had been misidentified. We indicate the distribution of this species in B.C. for the first time, and we present a corrected distribution map for Tephroseris yukonensis that includes our own collections
Data from: Vicariance, long-distance dispersal, and regional extinction–recolonization dynamics explain the disjunct circumpolar distribution of the arctic-alpine plant Silene acaulis
PREMISE OF THE STUDY: Many arctic-alpine species have vast geographic ranges, but these may encompass substantial gaps whose origins are poorly understood. Here we address the phylogeographic history of Silene acaulis, a perennial cushion plant with a circumpolar distribution except for a large gap in Siberia. METHODS: We assessed genetic variation in a range-wide sample of 103 populations using plastid DNA (pDNA) sequences and AFLPs (amplified fragment length polymorphisms). We constructed a haplotype network and performed Bayesian phylogenetic analyses based on plastid sequences. We visualized AFLP patterns using principal coordinate analysis, identified genetic groups using the program structure, and estimated genetic diversity and rarity indices by geographic region. KEY RESULTS: The history of the main pDNA lineages was estimated to span several glaciations. AFLP data revealed a distinct division between Beringia/North America and Europe/East Greenland. These two regions shared only one of 17 pDNA haplotypes. Populations on opposite sides of the Siberian range gap (Ural Mountains and Chukotka) were genetically distinct and appear to have resulted from postglacial leading-edge colonizations. We inferred two refugia in North America (Beringia and the southern Rocky Mountains) and two in Europe (central-southern Europe and northern Europe/East Greenland). Patterns in the East Atlantic region suggested transoceanic long-distance dispersal events. CONCLUSIONS: Silene acaulis has a highly dynamic history characterized by vicariance, regional extinction, and recolonization, with persistence in at least four refugia. Long-distance dispersal explains patterns across the Atlantic Ocean, but we found no evidence of dispersal across the Siberian range gap