Open Access. Powered by Scholars. Published by Universities.®

Ecology and Evolutionary Biology Commons™

Open Access. Powered by Scholars. Published by Universities.®

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 19711 - 19740 of 19750

Full-Text Articles in Ecology and Evolutionary Biology

Prosthennops Xiphodonticus, Sp. Nov.: A New Fossil Peccary From Nebraska, Erwin H. Barbour Apr 1925

Prosthennops Xiphodonticus, Sp. Nov.: A New Fossil Peccary From Nebraska, Erwin H. Barbour

Bulletin of the University of Nebraska State Museum (1924–2023)

During the field season of 1915, while collecting, a mile or two west of Valentine, Cherry County, Nebraska, Messrs. A. C. Whitford and J. B. Burnett secured for the Morrill-Maiben Palaeontological Collections, The Nebraska State Museum, The University of Nebraska, a finely preserved jaw of a small fossil hog, or peccary, belonging to the genus Frosthennops, accessioned No. 85-11-8-15B. & W.

The mandible under consideration was preserved in fine sand and is without blemish save that the condyle and coronoid are wanting. The dentition is perfect. In allusion to the sword-like tusks, which are unduly large, the species name xiphodonticus …


Sand Fulgurites From Nebraska Their Structure And Formative Factors, Abram E. Anderson Jan 1925

Sand Fulgurites From Nebraska Their Structure And Formative Factors, Abram E. Anderson

Bulletin of the University of Nebraska State Museum (1924–2023)

So much has been written during the past century on the origin, structure and occurrence of fulgurites, or lightning tubes, found in many parts of the world that it would seem as though little remains to be added to the literature on the subject; but the discovery of a considerable number of unusually large and complete specimens in Holt and Stanton Counties, Nebraska, which exhibit remarkable definition of the particular features that have occasioned so much controversy regarding their formative processes, has added an important type to the representatives of this phenomenon and afforded clearer interpretation of the origin of …


Skeletal Parts Of The Columbian Mammoth Elephas Maibeni, Sp. Nov., Erwin Hinckley Barbour Jan 1925

Skeletal Parts Of The Columbian Mammoth Elephas Maibeni, Sp. Nov., Erwin Hinckley Barbour

Bulletin of the University of Nebraska State Museum (1924–2023)

The skeletal parts of Elephas columbi are said to be unknown, although teeth, jaws, and skulls are common enough. Columbi is a mammoth of southern adaptation, hence its parts are found from Nebraska southward. Elephas columbi occurs abundantly throughout the State and many examples are preserved in the Nebraska State Museum, as will be seen in an accompanying list.


Tetrabelodon Abell, Sp. Nov., Erwin Hinckley Barbour Jan 1925

Tetrabelodon Abell, Sp. Nov., Erwin Hinckley Barbour

Bulletin of the University of Nebraska State Museum (1924–2023)

Brown County, Nebraska, which has been so prolific of long-jawed mastodons, has yielded another form which seems to be new and which may throw light on certain small tusks that occur where Tetrabelodon bones abound. Heretofore, we have considered these to be embryonic, but they show apparent wear, and in other respects they are enigmatic, and at best, atypical. Tetrabelodon tusks proper, however young, are typical, and are obviously tusks in miniature. The tusks in doubt are of varying lengths and about the diameter of one's thumb, but taper backwards, are worn to a bluntly oblique point, and are slightly …


Hackberry Conglomerate A New Nebraska Rock, Erwin Hinckey Barbour Jan 1925

Hackberry Conglomerate A New Nebraska Rock, Erwin Hinckey Barbour

Bulletin of the University of Nebraska State Museum (1924–2023)

In the cabinets of the Nebraska State Museum are several excellent rock specimens, which at first sight pass for pisolite, which they simulate. Scrutiny shows that they are hackberry seeds in sand, cemented by lime and clay into a firm, compact rock. The term hackberry conglomerate seems apropos.


Notes On Nebraska Fulgurites, Erwin Hinckley Barbour Jan 1925

Notes On Nebraska Fulgurites, Erwin Hinckley Barbour

Bulletin of the University of Nebraska State Museum (1924–2023)

Some six or eight years ago the writer contemplated a study of Nebraska fulgurites, both in the field and in the laboratory. In the meantime however, it proves to be superfluous for, after supplying Mr. A. E. Anderson, of the American Museum of Natural History, with certain material and data he proceeded in a masterful way on a technical inquiry, and it is with pleasure that, although delayed in publication, his findings follow in Bulletin 7 of the Nebraska State Museum. The present paper will deal as briefly as possible with the mode of occurrence and gross structure.


Sand Fulgurites From Nebraska Their Structure And Formative Factors, Abram E. Anderson Jan 1925

Sand Fulgurites From Nebraska Their Structure And Formative Factors, Abram E. Anderson

Bulletin of the University of Nebraska State Museum (1924–2023)

So much has been written during the past century on the origin, structure and occurrence of fulgurites, or lightning tubes, found in many parts of the world that it would seem as though little remains to be added to the literature on the subject; but the discovery of a considerable number of unusually large and complete specimens in Holt and Stanton Counties, Nebraska, which exhibit remarkable definition of the particular features that have occasioned so much controversy regarding their formative processes, has added an important type to the representatives of this phenomenon and afforded clearer interpretation of the origin of …


Manganese Fulgurites, Harold J. Cook Jan 1925

Manganese Fulgurites, Harold J. Cook

Bulletin of the University of Nebraska State Museum (1924–2023)

During August, 1924, while doing reconnaisance work near the head of Chugwater Creek, Wyoming, on the ranch of Mr. J. L. Jordon, the writer's attention was called to some unusual and interesting specimens found in a limited area, perhaps an acre or so, on the slope of the small butte flanking the Chugwater Valley. The hills of the region are of Tertiary age, the particular spot under consideration being Oligocene, the Brule stage, or Oreodon beds.


Elephas Scotti A New Primitive Mammoth From Nebraska, Erwin Hinckley Barbour Jan 1925

Elephas Scotti A New Primitive Mammoth From Nebraska, Erwin Hinckley Barbour

Bulletin of the University of Nebraska State Museum (1924–2023)

On February 18,1922, the mandible of an unusually primitive mammoth was secured for the palaeontological collections of Mr. Hector Maiben by Mr. E. T. Engle. The specimen was found in Aftonian gravel on the farm of Mr. E. J. Hartman, five miles south of Staplehurst, Seward County, Nebraska. It is numbered 18-2-22 in the accession book of the Nebraska State' Museum.


Elephas Scotti A New Primitive Mammoth From Nebraska, Erwin Hinckley Barbour Jan 1925

Elephas Scotti A New Primitive Mammoth From Nebraska, Erwin Hinckley Barbour

Bulletin of the University of Nebraska State Museum (1924–2023)

On February 18,1922, the mandible of an unusually primitive mammoth was secured for the palaeontological collections of Mr. Hector Maiben by Mr. E. T. Engle. The specimen was found in Aftonian gravel on the farm of Mr. E. J. Hartman, five miles south of Staplehurst, Seward County, Nebraska. It is numbered 18-2-22 in the accession book of the Nebraska State' Museum.


An American Fossil Giraffe Giraffa Nebrascensis, Sp. Nov., W. D. Matthew, E. H. Barbour Jan 1925

An American Fossil Giraffe Giraffa Nebrascensis, Sp. Nov., W. D. Matthew, E. H. Barbour

Bulletin of the University of Nebraska State Museum (1924–2023)

A fragment of the lower jaw of a large fossil mammal with two well-worn teeth was dug up in June 1918, at a depth of 20 feet, while digging a cess pool at Bradshaw, York County, Nebraska.


How To Study The Western Birds, Grace Mccormac French Jun 1924

How To Study The Western Birds, Grace Mccormac French

Jane Claire Dirks-Edmunds Documents

Originally a radio broadcast, this document explores the fraternal nature of bird watching. It was included in the papers of Dr. James A. Macnab, Dr. Jane Claire Dirks-Edmunds's mentor at Linfield College. The article mentions various books by bird-watching authorities and naturalists from around the Pacific Northwest.

Dirks-Edmunds, a 1937 graduate of Linfield, graduated from the University of Illinois in 1941; she returned to teach in the Biology department at Linfield from 1941-1974.


The Theory Of Spontaneous Generation, Arthur Thomas Kuesel Jun 1924

The Theory Of Spontaneous Generation, Arthur Thomas Kuesel

Bachelors’ Theses

The theories concerning the origin of life on this planet have been many and varied all down the ages. In the prescientific ages, if we may be allowed to designate those years as such, before science was as exacting and searching sit is now, practically all the theories advanced by the philosophers at the time have since been proven to be fallacies and all of them save one, the Theory of Spontaneous Generation have been discarded into the limbo of mistaken notions.


Extreme Evolution Is Absurd And Moderate Evolution Is Not Yet Established, Marie Georgiana Blommer Apr 1924

Extreme Evolution Is Absurd And Moderate Evolution Is Not Yet Established, Marie Georgiana Blommer

Bachelors’ Theses

In the world of literature and science many records containing startling theories are to be found. Among these is the doctrine of Evolution. Many assure us that Science compels us to believe in Evolution. An explanation of the terms must be clearly understood to avoid a fallacious use of terms. Professor Huxley, who follows Hume, declares that Science is "nothing but trained and organized commonsense." The term is applied to physical science or "that whose province is the observation of phenomena and inferences directly deducible from them." The term "Evolution" is often differently understood. In its literal sense it is …


A Preliminary Report On The Nebraska State Museum, Erwin H. Barbour Jan 1924

A Preliminary Report On The Nebraska State Museum, Erwin H. Barbour

Bulletin of the University of Nebraska State Museum (1924–2023)

The Nebraska State Museum has been established a sufficient number of years to make it widely known throughout the state, both by reputation and by personal visits. Incident to a growing clientele and an expanding correspondence, it is expedient that a concise circular letter be issued in bulletin form. Such a pamphlet can be promptly forwarded to inquirers and will offer obvious advantages over individual replies.


Root Behavior And Crop Yield Under Irrigation, Frank C. Jean, John E. Weaver Jan 1924

Root Behavior And Crop Yield Under Irrigation, Frank C. Jean, John E. Weaver

Papers of John E. Weaver (1884–1956)

More than half of the surface of the earth receives insufficient precipitation
for the most favorable growth of crops. The, best method of making up this deficiency is through the application of water by irrigation. Hence the economical use of irrigation water is one of the chief problems of agriculture in arid regions. Since much more land is available than can be irrigated by the supply of water, even when methods of greatest economy are employed, the welfare of these regions demands that the irrigation water be used as efficiently as possible (cf. Harris, 1916). It has been estimated that …


Some Field Instruments And Their Applications, G. W. Goldsmith Jan 1923

Some Field Instruments And Their Applications, G. W. Goldsmith

University Studies (University of Nebraska) (1888–1984)

Physiology and ecology depend for their constructive development largely upon the applications of physico-chemical concepts to living organisms and their environment, to their life processes, reactions, and interrelations. A concept is valuable biologically in so far as it can be applied and used as a tool for better understanding of the phenomena related to life. Ecology, as the study of the relations between organisms and their environment and of the interrelations of organisms, depends primarily upon the findings of physiology (Clements, 1905). But to apply physicochemical concepts and hence make them of value to the physiologist or ecologist commonly requires …


Variations In Cytology And Gross Morphology Of Taraxacum Ii. Senescence, Rejuvenescence, And Leaf Variation In Taraxacum, Paul B. Sears Jun 1922

Variations In Cytology And Gross Morphology Of Taraxacum Ii. Senescence, Rejuvenescence, And Leaf Variation In Taraxacum, Paul B. Sears

Papers in Ecology

The variability of Taraxacum has frequently been recorded in botanical literature without receiving much elucidation. It is less often an object of investigation than of conjecture and discussion. A few botanists have studied the effect of environmental factors upon Taraxacum, but their results have not cleared away taxonomic difficulties. Systematic botanists have either looked upon the variations in this genus as fluctuations or slight mutations, and then proceeded to lump or split as judgment might dictate. That life history exerts a profound influence upon form seems generally to have escaped attention.


Anthocyan Pigments, Paul B. Sears Jun 1922

Anthocyan Pigments, Paul B. Sears

Papers in Ecology

Noack has found rhamnose-free flavonol diglucosides to be much more abundant in green leaves than has generally been supposed. In such leaves as he studied he was able to establish the existence of flavonol-anthocyan in couples of similar glucosidal nature, but secured no evidence of aromatic nucleus composition in such cases. He suggests that these couples function as a reduction mechanism during photosynthesis.


Variations In Cytolgoy And Gross Morphology Of Taraxacum, I. Cytology Of Taraxacum Laevigatum, Paul B. Sears Apr 1922

Variations In Cytolgoy And Gross Morphology Of Taraxacum, I. Cytology Of Taraxacum Laevigatum, Paul B. Sears

Papers in Ecology

These investigations are the outgrowth of a study, begun in 1914 at the instance of the late Professor C. E. Bessey, of parthenogenesis in Taraxacum vulgare (Lam.) Schrk. and T. laevigatum ( Willd.) DC. These two species are the common ones in central United States, being respectively designated as Leontodon taraxacum L. and L. erythrospermum (Andrz.) by Britton and Brown (3). In 1917 the existence of ameiotic parthenogenesis in both species was confirmed (23) and certain pollen abnormalities briefly described. These abnormalities have invited more critical analysis as a means of throwing light upon certain phases of variation …


Vegetation Mapping, Paul B. Sears Apr 1921

Vegetation Mapping, Paul B. Sears

Papers in Ecology

The value of accurate maps of native vegetation as a basis for very practical generalizations can not be questioned. It is obvious that an essential condition for getting accurate maps of large areas is the existence of precise maps of smaller component ones. At present very few precise local maps are available, but it is to be hoped that botanists throughout the country will begin to supplement the efforts of a few of their number who are doing map work of permanent and general' value.


Variation In Taraxacum, Paul B. Sears Feb 1921

Variation In Taraxacum, Paul B. Sears

Papers in Ecology

To the editor of Science: Since several species of Taraxacum are parthenogenetic and at the same time highly variable they have. looked like tempting material for the study of certain phases of genetics. Moreover their "polysnorphy," as well as that of other parthenogenetic plants, has served as a partial basis for well-known attempts to explain parthenogenesis as due to hybridization.


The Ecological Relations Of Roots, John E. Weaver Jan 1919

The Ecological Relations Of Roots, John E. Weaver

Papers of John E. Weaver (1884–1956)

Although considerable progress has been made in the study of root systems of desert plants (Cannon, 1911, 1913; Markle, 1917), very little information is available concerning the roots of other native species. During 1914 the writer investigated the root systems of the prairie plants of southeastern Washington, where the annual precipitation is only 21.6 inches and occurs mostly in the period of rest: Since that time it has been planned to make a comparative study of the roots of prairie plants growing in a more humid region and where the precipitation occurs mostly during the season of plant growth. The …


Climate And Plant Growth In Certain Vegetative Associations, Arthur W. Sampson Oct 1918

Climate And Plant Growth In Certain Vegetative Associations, Arthur W. Sampson

Aspen Bibliography

The relation of climate to the growth and development of vegetation is of profound importance in both practical and experimental agriculture. It is extremely useful to know the cause of successful growth and establishment, or of partial success or failure, of various species in different plant associations and under widely contrasted climatic conditions. The climatic requirements of various plant types are largely responsible for the results obtained in the case of experimental seedings and plantings of most species. Once the adverse climatic factors are definitely known, failures with plants may be largely avoided by the judicious selection of sites or …


The Story Of Aspen, Enos Mills Feb 1918

The Story Of Aspen, Enos Mills

Aspen Bibliography

No abstract provided.


Changing Diatoms Of Devils Lake, Clarence Elmore Feb 1918

Changing Diatoms Of Devils Lake, Clarence Elmore

School of Biological Sciences: Faculty Publications

During the summer of 1915 I spent some time at the Biological Station of the University of North Dakota at Devils Lake, investigating the diatoms of the lake. Before this considerable diatom material had been sent to me by Dr. R. T. Young of the University, who is conducting the biological survey of the lake.
The immediate practical object in the survey is to determine the organisms in the lake in relation to the fish that might be able to subsist upon them, and diatoms being the most abundant of microscopic plants, deserve special attention in this connection. At present …


Further Studies In The Ecotone Between Prairie And Woodland, R. J. Pool, J. E. Weaver, F. C. Jean Jan 1918

Further Studies In The Ecotone Between Prairie And Woodland, R. J. Pool, J. E. Weaver, F. C. Jean

University Studies (University of Nebraska) (1888–1984)

A series of intensive investigations of the ecological features of the tension zone between prairie and woodland in the Mississippi valley was begun by Weaver and Thiel in 1915. These studies were continued for two seasons in Minnesota and were also extended to the prairies of eastern Nebraska in 1916. These investigations represent the first attempt to attack the prairie-forest problem on a comprehensive scale by means of the quantitative methods of modern ecology. Some of the results secured from these studies have been published as the first paper of a series planned to deal with critical investigations in the …


[Book Review Of] Adaptation In Metapopulations: How Interaction Changes Evolution, By Michael J. Wade., David C. Queller Jun 1917

[Book Review Of] Adaptation In Metapopulations: How Interaction Changes Evolution, By Michael J. Wade., David C. Queller

Biology Faculty Research

Adaptation in Metapopulations: How Interaction Changes Evolution. By Michael J. Wade. Chicago (Illinois): University of Chicago Press . $120.00 (hardcover); $40.00 (paper). vii + 260 p.; ill.; index. ISBN: 978-0-226-12956-3 (hc); 978-0-226-12973-0 (pb); 978-0-226-12987-7 (eb). 2016.


Amiotic Parthenogenesis In Taraxacum Vulgare (Lam.) Scrk. And Traxacum Laevigatum (Willd.) Dc., Paul B. Sears Jan 1917

Amiotic Parthenogenesis In Taraxacum Vulgare (Lam.) Scrk. And Traxacum Laevigatum (Willd.) Dc., Paul B. Sears

Papers in Ecology

The work of which the results are here offered, awaiting detailed presentation in a paper to follow, was begun at the University of Nebraska in 1914, under the direction of the late Dr. Charles E. Bessey. The two species of dandelion which have been studied are respectively the Leontodon taraxacum and the L. erythrospermum of the Second Edition of Britton and Brown's Illustrated Flora: the nomenclature used in the title of this paper has been adopted on the basis of evidence presented in the monograph of the genus Taraxacum by Handel-Mazetti.


Evaporation And Plant Zones In The Cedar Point Marsh, Paul B. Sears Jan 1916

Evaporation And Plant Zones In The Cedar Point Marsh, Paul B. Sears

Papers in Ecology

Yapp in trying to account for the xerophytic structure of marsh plants by means of evaporation studies has shown a definite correlation to exist between the strata of marsh vegetation and rates of evaporation at corresponding levels. The following studies were made in an attempt to discover what additional correlations, if any, exist between distribution of marsh plants and the evaporational power of the air at different portions of the habitat. While the exact quantitative significance of such work as the following may be brought into question, as it often is, the striking results obtained by Transeau, Livingston, Fuller, Weaver, …