Life Sciences Commons^™

Phylogenetic Hypotheses For The Monocotyledons Constructed From RbcL Sequence Data, James F. Smith

Biology Faculty Publications and Presentations

DNA sequences for the plastid locus that encodes the large subunit if ribulose 1.5 bisphosphate carboxylase/oxygenase (rbcL) were determined for 18 species of monocotyledons in 15 families. These data were analyzed together with sequences for 60 other monocot species in a total of 52 families by the maximum likelihood method producing one, presumably optimal, topology. An additional 26 species were added (104 total monocot species) and analyzed by the parsimony method with an outgroup of 18 dicot species producing 109 trees of 3,932 steps. The rbcL data show at least moderate support for seven lineages corresponding to …

Phylogenetic Analysis Of The Zingiberales Based On RbcL Sequences, James F. Smith, W. John Kress, Elizabeth A. Zimmer

Biology Faculty Publications and Presentations

Morphological data have been used previously to construct phylogenies of the eight families of the Zingiberales one of the most widely accepted monophyletic groups of flowering plants. To provide additional support for phylogenetic relationships within the order, and placement of the order among monocots, we present a parsimony analysis of DNA sequences from the chloroplast-encoded gene, rbcL, for 21 species of Zingiberales and proposed relatives. Five analyses with equal, and differential weights were performed. All analyses resulted in the same most parsimonious tree for taxa within the Zingiberales and the immediate outgroup. The closest sister group to the Zingiberales …

The Genus Urochloa (Poaceae: Paniceae) In Texas, Including One Previously Unreported Species For The State, J. K. Wipff, Robert I. Lonard, Stanley D. Jones, Stephan L. Hatch

Biology Faculty Publications and Presentations

Urochloa is represented in Texas by three species, U. mosambicensis, U. panicoides, and U. reptans. Urochloa mosambicensis is being reported new for Texas. Urochloa panicoides has recently been reported in the state and is listed in the Federal Noxious Weed Act. Urochloa reptans has been recognized in Texas and the U. S. as Panicum reptans or, more recently, Brachiaria reptans. A key to distinguish related genera, a key to the species of Urochloa in Texas, species descriptions, and their distribution in Texas are provided.

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Urochloa está representada en Texas por tres especies, U. mosambicensis, U. panicoides y U. reptans. …

Phylogenetics Of Seed Plants: An Analysis Of Nucleotide Sequences From The Plastid Gene RbcL, James F. Smith

Biology Faculty Publications and Presentations

We present the results of two exploratory parsimony analyses of DNA sequences from 475 and 499 species of seed plants. respectively, representing all major taxonomic groups. The data are exclusively from the chloroplast gene rbcL, which codes for the large subunit of ribulose-l .5-bisphosphate carboxylase/ oxygenase (RuBisCO or RuBPCase). We used two different state-transformation assumptions resulting in two sets of cladograms: (i) equal-weighting for the 499-taxon analysis; and (ii) a procedure that differentially weights transversions over transitions within characters and codon positions among characters for the 475-taxon analysis. The degree of congruence between these results and other molecular. as …

Biology Of The Palo Alto Battlefield Site: A Summary, Norman L. Richard, Alfred Richardson

Biology Faculty Publications and Presentations

No abstract provided.

Comparison Of The Effects Of The Severe Freezes Of 1983 And 1989 On Native Woody Plants In The Lower Rio Grande Valley, Texas, Robert I. Lonard, Frank W. Judd

Biology Faculty Publications and Presentations

Freeze damage to native woody plants was assessed at the same four sites in the lower Rio Grande Valley, Texas, in 1983 and 1989. The number of severely damaged species was greater in 1989 possibly because temperatures in 1989 were lower and longer in duration below freezing versus 1983. Thirty0five species (48.6%) had the same damage index value for the two freezes, and 24 (33.3%) species showed no damage in either year. More than half of the 72 species analyzed (55.5% in 1983 and 51.3% in 1989) showed no damage or only leaf damage, indicating most of the native woody …

Notes On The Vegetation And Flora Of North Padre Island, Texas, E. Glenn Carls, Robert I. Lonard, Dennis B. Fenn

Biology Faculty Publications and Presentations

No abstract provided.

Woody Plants Of The Lower Rio Grande Valley, Texas, Robert I. Lonard, James H. Everitt, Frank W. Judd

Biology Faculty Publications and Presentations

Description of Common Vegetation of Lower Rio Grande Valley.

Temporal Patterns Of Nectar And Pollen Production In Aralia Hispida: Implications For Reproductive Success, James D. Thomas, Mary A. Mckenna, Mitchell B. Cruzan

Biology Faculty Publications and Presentations

Large plants of Aralia hispida present their pollen and nectar in hundreds of small flowers than open sequentially over 2—3 wk in a pattern of synchronized protandry that alternates male and female phases. The primary pollinators, bumble bees, are able to discover individual plants with elevated levels of either nectar or pollen, and to return to them more often than to less rewarding plants. Both pollen and nectar are presented gradually over time in such a way as to favor traplining behavior by the bees, with many, frequent visits. In controlled environments, lifetime sugar production per flower varies among plants, …

The Impact Of Weather On Kingbird Foraging Behavior, Michael T. Murphy

Biology Faculty Publications and Presentations

Foraging data on Eastern Kingbirds (Tyrannus tyrannus) were collected during the early breeding season in eastern Kansas to test the hypothesis that foraging rate and other aspects of foraging behavior vary with weather. Foraging characteristics of five additional kingbird species were also examined to assess Fitzpatrick's (1980) generalization that kingbirds (Tyrannus spp.) are aerial hawking specialists. In Eastern Kingbirds, total foraging rate was independent of air temperature, cloud cover, wind speed, and time of day, but the rate of aerial hawking varied directly with air temperature and inversely with cloud cover (both P < 0.05). Effects of the two variables were additive. The percentage of foraging movements that were aerial hawks also increased with temperature and declined with cloud cover, and, hover-gleaning and perch-to-ground sallying were observed mainly during cloudy weather. Sally (i.e., foraging flight) distance correlated directly with perch height and air temperature, and large insects were captured almost exclusively in long upward or horizontal flights. I interpret these data to indicate that foraging behavior and the capture of large, flying insects depends on weather because of how it affects the activity of insect prey. Foraging data on kingbirds support Fitzpatrick's generalization, but the relative use of aerial hawking varies considerably among species. Resident Tropical Kingbirds( T. melancholicus) are the most specialized foragers, whereas the migrant and widely distributed Eastern Kingbird appears to be the most generalized. Certain habitats also appear to favor the use of particular foraging methods (e.g., outward striking in grasslands and perch-to-ground sallying in drier, open habitats).

Body Size, Nest Predation, And Reproductive Patterns In Brown Thrashers And Other Mimids, Michael T. Murphy, Robert C. Fleischer

Biology Faculty Publications and Presentations

We describe the breeding biology of Brown Thrashers (Toxostoma rufum) in Kansas, and combine this with data from other temperate-zone breeding Mimidae to characterize reproductive patterns in this group. Brown Thrashers produced clutches of 3 to 6 eggs, but clutches of 4 predominated. Most pairs raised 2 broods per year. Incubation required between 13 and 14 days, and hatching was usually asynchronous. Though sample size was small, asynchrony appeared to increase in frequency towards the end of the breeding season. Nestlings grew rapidly, and in 10 days or less most pre-fledgingg rowthw as completed. Young fledgedn ormallya t 11 days …

Body Size And Condition, Timing Of Breeding, And Aspects Of Egg Production In Eastern Kingbirds, Michael T. Murphy

Biology Faculty Publications and Presentations

Variation in timing of breeding in Eastern Kingbirds (Tyrannus tyrannus) was correlated only weakly with external morphological characters, but was correlated positively and significantly with estimates of body size based on measurements of skeletons and muscle weights. Small females apparently held a reproductive advantage in being able to mobilize resources for reproduction before large females. Egg weight was independent of all measures of female size, but was directly and significantly (P = 0.03) correlated with standard flight muscle weight, a relative index of body condition. Egg size was thus a function more of female body condition than size. On average, …

Brood Parasitism Of Eastern Kingbirds By Brown-Headed Cowbirds, Michael T. Murphy

Biology Faculty Publications and Presentations

Understanding why brood parasites lay eggs in the nests of hosts that reject eggs is hampered by insuf-ficient data on the frequency with which parasites lay in rejecter nests, and by ignorance of which in-dividuals practice this seemingly inappropriate be-havior. Parasitism rates of rejecters can be deter-mined only when host nests are observed during egg laying because most parasite eggs are rejected rapidly (e.g. Scott 1977). Even then, however, a certain per-centage of parasitized nests may go undetected. De-termining the selective value of host defense mech-anisms also depends on knowledge of the frequency of parasitism, and the amount of reproductive …

Esenbeckia Berlandieri (Rutaceae) Rediscovered In Extreme Southern Texas, Michael R. Heep, Robert I. Lonard

Biology Faculty Publications and Presentations

No abstract provided.

Sea Urchins From The Brazos Santiago Pass Jetty, South Padre Island, Richard R. Fairchild, Lazern O. Sorensen

Biology Faculty Publications and Presentations

Data on occurrence and distribution of sea urchins (Echinoidea) are presented for the Brazos Santiago Pass jetty on South Padre Island, Texas. Echinometra lucunter is recorded from the Texas coast.

Factors Influencing Cellulolytic Activity Of The Soil Fungus, Aspergillus Candidus, Jacobo Ortega, Ernest J. Baca

Biology Faculty Publications and Presentations

Effects of pH, incubation time, nitrogen source and carbohydrate source upon production of carboxymethyl cellulase by Aspergillus candidus grown in liquid medium were studied. Maximal cellulase activity per unit of protein occurred in culture fluids with a pH of 5.5, after 10 days of cultivation of the fungus. Ammonium nitrate supported the highest production of the enzyme. However, in the nitrogen-source test, highest accumulation of extracellular protein was found in fluids from cultures with urea as the nitrogen source. Cotton fibers produced the greatest gain in cellulase activity when the carbohydrate source was incremented from 0.5 to 1.0 percent. The …

Effects Of A Severe Freeze On Native Woody Plants In The Lower Rio Grande Valley, Texas, Robert I. Lonard, Frank W. Judd

Biology Faculty Publications and Presentations

The effects of a severe freeze in December, 1983 on the native plants of the lower Rio Grande Valley, Texas were determined for 75 species. Damage was initially assessed by examining leaves, apical meristems, and cambial tissues of stems. Initial assessments were confirmed by surveys in the spring when new leaves were present. Forty-three species were either undamaged or had only minor leaf damage. Twenty-two species with damaged leaves had intact apical meristems or showed evidence of damage for less than 10 cm below the apical meristem. Three species, Leucaena pulverulenta, Cordia boissieri, and Karwinskia humboldtiana, had more extensive damage, …

Nest Success And Nesting Habits Of Eastern Kingbirds And Other Flycatchers, Michael T. Murphy

Biology Faculty Publications and Presentations

Patterns of nest placement and its relationship to nest success in the Eastern Kingbird (Tyrannus tyrannus) were studied in populations breeding in New York and Kansas. Data were augmented with information on nest placement in other open-nesting tyrannids in order to examine the hypothesis that these flycatchers place their nests chiefly so as to conceal them from predators. Nesting success was significantly greater in New York than in Kansas but was relatively high in both populations, as is apparently true of North American breeding flycatchers in general. Geographic variation in nest placement in the Eastern Kingbird was relatively small and …

Clutch Size In The Eastern Kingbird: Factors Affecting Nestling Survival, Michael T. Murphy

Biology Faculty Publications and Presentations

Observational and experimental procedures were used to evaluate the potential importance of brood size and weather on the evolution of clutch size in the Eastern Kingbird. Modal clutch size was three eggs, yet broods of four were most productive. Nestling size varied inversely with brood size, so that "nestling quality" was lower in broods of four than in broods of three. Asymptotic weight of nestlings in broods of three was directly and significantly correlated with ambient air temperature, followed by hatch order. Because larger broods were being fed during a period of relatively cool and wet weather, the effects of …

Habitat Selection Related To Resource Availability Among Cavity-Nesting Birds, Timothy Brush

Biology Faculty Publications and Presentations

Variation in snag species and abundance appeared to explain most of the habitat selection patterns observed in five cavity-nesting riparian species over a three-year period. All species except Ash-throated Flycatchers were most common in areas with cottonwood or willow snags, which have relatively soft wood and are preferred nest sites. Classification of habitats on the basis of nest-site characteristics was useful and should be considered in other habitat selection studies.

The Terrestrial Flora Of South Padre Island, Texas, Robert I. Lonard, Frank W. Judd

Biology Faculty Publications and Presentations

The primary aim of this work is to enable the user to identify the flowering plants of South Padre Island; however, it should be useful for identification of plants on other Texas barrier islands and on the Mexican barrier islands. We hope that the keys will aid teachers, students, coastal zone managers, and individuals conducting environmental impact assessments.

Phytogeography Of South Padre Island, Texas, Robert I. Lonard, Frank W. Judd

Biology Faculty Publications and Presentations

The phytogeographic affinities of the native flora of South Padre Island, Texas, are analyzed and the probable dispersal agent(s) for each species identified. The native flora consists of 99 species and 44% of the species also occur on the adjacent Texas mainland; 28% of the native species have tropical affinities. Only three species have probably dispersed from the island to the mainland. Two species may be endemic to Padre Island and the Tamaulipan barrier islands. Most of the tropical species have reached the island by oceanic drift, but birds are the most important dispersal agent for the native species. Man …

Cellulase Activities Of Soil Fungi, Jacobo Ortega

Biology Faculty Publications and Presentations

The cellulase activities of 8 isolates of fungi obtained from agricultural soils of Hidalgo County, TX were investigated by measuring the changes in the viscosity of a buffered solution of carboxymethylcellulose (CMC), produced by the fluids obtained from liquid cultures of these isolates. The change in the viscosity of the reaction mixture incubated at constant temperature (30 C) was measured with Cannon-Fenske routine viscometers. A buffered cellulase solution was used as a control.

Due to the variability that existed among the isolates investigated, it was possible to select active producers of cellulase with the method followed in this investigation. The …

Annotated Checklist Of The Flowering Plants Of South Padre Island, Texas, Robert I. Lonard, Frank W. Judd, Sammie L. Sides

Biology Faculty Publications and Presentations

This study catalogues the flowering plants of South Padre Island, Texas. A total of 207 species in 47 families is listed. The abundance and ecological distribution of each taxon are noted. Comparisons are made with the flora of Mustang Island, Texas. Ninety-three species, 96 genera and 36 families are common to both islands. Three families, Compositae, Gramineae and Leguminosae, contain large shares of the total number of species on both islands. Apparently, much of the floral diversity is due to the presence of a large number of species that are represented by small populations.

Reinstatement Of The Genus Tiquilia (Boraginaceae: Ehretioideae) And Descriptions Of Four New Species, Alfred Richardson

Biology Faculty Publications and Presentations

No abstract provided.

Recommended Vegetable Varieties For The Lower Rio Grande Valley Of Texas, J. B. Corns

Biology Faculty Publications and Presentations

No abstract provided.