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Full-Text Articles in Life Sciences

The Finch Effect: Evolutionary Metaphors And Illiberal Democracy In Central And Eastern Europe, Abigail Woodfield Aug 2019

The Finch Effect: Evolutionary Metaphors And Illiberal Democracy In Central And Eastern Europe, Abigail Woodfield

Claremont-UC Undergraduate Research Conference on the European Union

In recent years, several states in Central and Eastern Europe have seen democratic digression. Such illiberal resurgences came as a surprise to the many political scientists who assumed that the future of these states was democratic. Indeed, after the fall of the Soviet Union, the world largely regarded liberal democracy as the predominant system of government. The future seemed bright, and it was tempting to understand that future in evolutionary terms—just as humans evolved under natural selection to become the dominant species, democracy had survived a similar competition and defeated all other systems of government to become the dominant regime. …


Evolution Of Spur-Length Diversity In Aquilegia Petals Is Achieved Solely Through Cell-Shape Anisotropy, Joshua R. Puzey, Sharon J. Gerbode, Scott A. Hodges, Elena M. Kramer, L. Mahadevan Nov 2011

Evolution Of Spur-Length Diversity In Aquilegia Petals Is Achieved Solely Through Cell-Shape Anisotropy, Joshua R. Puzey, Sharon J. Gerbode, Scott A. Hodges, Elena M. Kramer, L. Mahadevan

All HMC Faculty Publications and Research

The role of petal spurs and specialized pollinator interactions has been studied since Darwin. Aquilegia petal spurs exhibit striking size and shape diversity, correlated with specialized pollinators ranging from bees to hawkmoths in a textbook example of adaptive radiation. Despite the evolutionary significance of spur length, remarkably little is known about Aquilegia spur morphogenesis and its evolution. Using experimental measurements, both at tissue and cellular levels, combined with numerical modelling, we have investigated the relative roles of cell divisions and cell shape in determining the morphology of the Aquilegia petal spur. Contrary to decades-old hypotheses implicating a discrete meristematic zone …


A Mathematician Weighs In On The Evolution Debate, Kris H. Green Jul 2011

A Mathematician Weighs In On The Evolution Debate, Kris H. Green

Journal of Humanistic Mathematics

There are a variety of reasons underlying the lack of public acceptance for the theory of evolution in the United States. An overlooked cause is related to problems with the mathematics curriculum in the K-12 setting. In this essay, we examine this relationship and propose changes to the mathematics curriculum that could improve mathematical thinking while also providing a basis for understanding theories, like evolution, that are poorly understood.


Wood Anatomy Of Family Salvadoraceae From The Indian Subcontinent With Special Reference To The Ultrastructure Of The Vessel Wall, Vishakha Saxena, Sangeeta Gupta Mar 2011

Wood Anatomy Of Family Salvadoraceae From The Indian Subcontinent With Special Reference To The Ultrastructure Of The Vessel Wall, Vishakha Saxena, Sangeeta Gupta

Aliso: A Journal of Systematic and Floristic Botany

The present study describes the wood microstructure of Azima tetracantha, Salvadora oleoides, and S. persica, the members of family Salvadoraceae represented in the Indian Subcontinent. An identification key based on wood anatomical features has been developed for the separation of the species. SEM studies revealed the presence of vesturing in intervessel pits of Salvadora.


Descriptive Anatomy And Evolutionary Patterns Of Anatomical Diversification In Adenia (Passifloraceae), David J. Hearn May 2009

Descriptive Anatomy And Evolutionary Patterns Of Anatomical Diversification In Adenia (Passifloraceae), David J. Hearn

Aliso: A Journal of Systematic and Floristic Botany

To understand evolutionary patterns and processes that account for anatomical diversity in relation to ecology and life form diversity, anatomy of storage roots and stems of the genus Adenia (Passifloraceae) were analyzed using an explicit phylogenetic context. Over 65,000 measurements are reported for 47 quantitative and qualitative traits from 58 species in the genus. Vestiges of lianous ancestry were apparent throughout the group, as treelets and lianous taxa alike share relatively short, often wide, vessel elements with simple, transverse perforation plates, and alternate lateral wall pitting; fibriform vessel elements, tracheids associated with vessels, and libriform fibers as additional tracheary elements; …


Integrating Development And Evolution In Psychology: Looking Back, Moving Forward, David S. Moore Dec 2008

Integrating Development And Evolution In Psychology: Looking Back, Moving Forward, David S. Moore

Pitzer Faculty Publications and Research

This work is the editorial for a special edition of New Ideas in Psychology titled Integrating Development and Evolution in Psychology.


Individuals And Populations: How Biology's Theory And Data Have Interfered With The Integration Of Development And Evolution, David S. Moore Dec 2008

Individuals And Populations: How Biology's Theory And Data Have Interfered With The Integration Of Development And Evolution, David S. Moore

Pitzer Faculty Publications and Research

Research programs in quantitative behavior genetics and evolutionary psychology have contributed to the widespread belief that some psychological characteristics can be “inherited” via genetic mechanisms. In fact, molecular and developmental biologists have concluded that while genetic factors contribute to the development of all of our traits, non-genetic factors always do too, and in ways that make them no less important than genetic factors. This insight demands a reworking of the Modern Evolutionary Synthesis, a theory that defined evolution as a process involving changes in the frequencies of genes in populations, and that envisioned no role for experiential factors now known …


Dicliny In Bouteloua (Poaceae: Chloridoideae): Implications For The Evolution Of Dioecy, Michael S. Kinney, J. Travis Columbus, Elizabeth A. Friar Dec 2007

Dicliny In Bouteloua (Poaceae: Chloridoideae): Implications For The Evolution Of Dioecy, Michael S. Kinney, J. Travis Columbus, Elizabeth A. Friar

Aliso: A Journal of Systematic and Floristic Botany

The New World grass genus Bouteloua (Chloridoideae: Cynodonteae) comprises 57 species, 13 of which produce unisexual spikelets and hence are diclinous. Andromonoecy, gynodioecy, monoecy, trimonoecy, and dioecy all occur in the genus, and ten species are known to express more than one of these breeding systems. Employing a phylogenetic estimate based on parsimony analysis of DNA sequences from the ITS (nrDNA) and trnL–F (cpDNA) regions representing 35 species of Bouteloua, including ten of 13 diclinous species, we used parsimony character state reconstructions to investigate the evolution of unisexual spikelets and breeding systems. Our specific goals were to estimate …


A Comparison And Combination Of Plastid Atpb And Rbcl Gene Sequences For Inferring Phylogenetic Relationships Within Orchidaceae, Kenneth M. Cameron Jan 2006

A Comparison And Combination Of Plastid Atpb And Rbcl Gene Sequences For Inferring Phylogenetic Relationships Within Orchidaceae, Kenneth M. Cameron

Aliso: A Journal of Systematic and Floristic Botany

Parsimony analyses of DNA sequences from the plastid genes atpB and rbcL were completed for 173 species of Orchidaceae (representing 150 different genera) and nine genera from outgroup families in Asparagales. The atpB tree topology is similar to the rbcL tree, although the atpB data contain less homoplasy and provide greater jackknife support than rbcL alone. In combination, the two-gene tree recovers five monophyletic clades corresponding to subfamilies within Orchidaceae, and fully resolves them with moderate to high jackknife support as follows: Epidendroideae are sister to Orchidoideae, followed by Cypripedioideae, then Vanilloideae, and with …


A Nuclear Rdna Phylogeny Of Smilax (Smilacaceae), Kenneth M. Cameron, Chengxin Fu Jan 2006

A Nuclear Rdna Phylogeny Of Smilax (Smilacaceae), Kenneth M. Cameron, Chengxin Fu

Aliso: A Journal of Systematic and Floristic Botany

Smilacaceae are a taxonomically confused, cosmopolitan family of Liliales characterized by climbing habit, reticulate leaf venation, paired petiolar tendrils, unisexual flowers, and superior ovaries. Deviations from this generalized morphology have led to the division of Smilacaceae into at least seven different genera and five sections within the large genus Smilax. In particular, taxa with connate tepals (Heterosmilax), more than six stamens (Pleiosmilax, Oligosmilax), or herbaceous habit (Hemexia) have been variously classified. Using DNA sequences of 96 taxa from the nuclear rDNA ITS gene region, parsimony analyses provide moderate resolution, but generally poor bootstrap support …


Phylogeny And New Intrageneric Classification Of Allium (Alliaceae) Based On Nuclear Ribosomal Dna Its Sequences, Nikolai Friesen, Reinhard M. Fritsch, Frank R. Blattner Jan 2006

Phylogeny And New Intrageneric Classification Of Allium (Alliaceae) Based On Nuclear Ribosomal Dna Its Sequences, Nikolai Friesen, Reinhard M. Fritsch, Frank R. Blattner

Aliso: A Journal of Systematic and Floristic Botany

The internal transcribed spacer region (ITS) of nuclear ribosomal DNA was sequenced from 195 representative species of Allium, two species of Nothoscordum, and one species each of lpheion, Dichelostemma, and Tulbaghia. Within the Allium species the lengths of the ITS regions were in a range from 612 to 661 base pairs and pairwise genetic distances reached up to 46%. The ITS data supported the inclusion of Nectaroscordum, Caloscordum, and Milula into Allium. Subgenera Rhizirideum and Allium, as well as sects. Reticulatobulbosa and Oreiprason were non-monophyletic taxa. Based on the phylogenetic relations, a new classification of genus Allium consisting of 15 …


The Role Of Phylogenetic Constraints In The Evolution Of Pollination Mechanisms In Iridaceae Of Sub-Saharan Africa, Peter Bernhardt, Peter Goldblatt Jan 2006

The Role Of Phylogenetic Constraints In The Evolution Of Pollination Mechanisms In Iridaceae Of Sub-Saharan Africa, Peter Bernhardt, Peter Goldblatt

Aliso: A Journal of Systematic and Floristic Botany

Novel, specialized systems exploiting bibionid flies, oil-collecting bees, wasps, or crepuscular settling moths as pollen vectors are added to the range of recorded pollination mechanisms in sub-Saharan Africa Iridaceae, while knowledge of the pollination of previously understudied genera such as Aristea, Bahiana, Ferraria, Hesperantha, and Tritoniopsis is expanded. The pollination of 357 species of the sub-Saharan African Iridaceae now includes 17 discrete systems. Based on repetitive interlinked suites of floral attractants and rewards we now infer pollination mechanisms for an additional 883 species. Many pollination systems recur in genera containing > 10 species. The ancestral pollination in African Iridaceae, and …


Trying To Fix The Development In Evolutionary Developmental Psychology, David S. Moore Jul 2003

Trying To Fix The Development In Evolutionary Developmental Psychology, David S. Moore

Pitzer Faculty Publications and Research

If we agree for a moment that there is such a thing as human nature, we immediately encounter an extraordinarily thorny question: Where does our nature come from? This question drives David Bjorklund and Anthony Pellegrini’s new book The Origins of Human Nature: Evolutionary Developmental Psychology. The question is so challenging, in part, because human nature reflects at least two conceptually distinct processes: evolution and development. The former, which operates across generations, allows the continued existence of characteristics that permitted survival and reproduction in our ancestors; the latter, which operates during a person’s lifetime, contributes to the appearance of …


A Coalescent Approach To Chloroplast Genome Relationships Within And Between Populations Of Pinus Devoniana In Mexico, Jennifer A. Matos Jan 1998

A Coalescent Approach To Chloroplast Genome Relationships Within And Between Populations Of Pinus Devoniana In Mexico, Jennifer A. Matos

Aliso: A Journal of Systematic and Floristic Botany

Pinus devoniana, a member of the Pinus montezumae complex (Ponderosae) of Mexico and Central America occurs as scattered populations from the western states of Jalisco and Nayarit to Chiapas in the east. Populations within regions, i.e., western or eastern Mexico, are separated by from 75 to 300 km, while the eastern and western populations are more that 700 km apart. Levels of gene flow between populations within regions and between eastern and western Mexico are assessed using the paternally inherited chloroplast genome as a marker. Twenty-five polymorphic restriction chloroplast sites were found in the 175 individuals surveyed; …


The Linnaean Hierarchy And The Evolutionization Of Taxonomy, With Emphasis On The Problem Of Nomenclature, Kevin De Queiroz Jan 1997

The Linnaean Hierarchy And The Evolutionization Of Taxonomy, With Emphasis On The Problem Of Nomenclature, Kevin De Queiroz

Aliso: A Journal of Systematic and Floristic Botany

During the post-Darwinian history of taxonomy, the Linnaean hierarchy has maintained its role as a means for representing hierarchical taxonomic relationships. During the same period, the principle of descent has taken on an increasingly important role as the basis for reformulated versions of fundamental taxonomic concepts and principles. Early in this history, the principle of descent provided an explanation for the existence of taxa and implied a nested, hierarchical structure for taxonomic relationships. Although an evolutionary explanation for taxa contradicted the Aristotelian context within which the Linnaean hierarchy was developed, the nested, hierarchical structure of taxonomic rela· tionships implied by …


Does The Monocot Mode Of Leaf Development Characterize All Monocots?, Geeta Bharathan Jan 1996

Does The Monocot Mode Of Leaf Development Characterize All Monocots?, Geeta Bharathan

Aliso: A Journal of Systematic and Floristic Botany

Patterns of early leaf development in monocots are analyzed in a phylogenetic context. Recent developmental and phylogenetic studies enable this reevaluation of the leaf base model of the developing monocot leaf. Two questions are addressed: a) is the presence of the Vorläuferspitze (fore-runner tip) invariably correlated with development of the lamina from the lower leaf zone? and b) was the ancestral monocot characterized by the leaf base mode of development? Scanning electron microscopic observations are made of young primorida using the mold and cast method. These data are combined with data from the literature and examined in a phylogenetic context …


Integrating Cellular And Molecular Approchaes Into Studies Of Development And Evolution: The Issue Of Morphological Homology, Andrés Collazo, Scott E. Fraser Jan 1996

Integrating Cellular And Molecular Approchaes Into Studies Of Development And Evolution: The Issue Of Morphological Homology, Andrés Collazo, Scott E. Fraser

Aliso: A Journal of Systematic and Floristic Botany

Understanding the development and evolution of complex morphological characters requires broad, multidisciplinary approaches. By combining biological imaging, phylogenetic analyses, embryological manipulations and additional modem molecular techniques (e.g., whole mount in situ hybridization), we can address fundamental questions, such as the determination of homology. Many of the novel structures that evolved in vertebrates and distinguish them from their ancestors (such as jaws and the mechanosensory lateral line) are derived embryonically from two migratory ectodermal tissues, neural crest and/or various epidermal placodes. In particular, time-lapse cinematography of fluorescently labeled cells in living Xenopus and fish embryos has proved a powerful technique, revealing …


Body Size In Amblyrhiza Inundata (Rodentia, Caviomorpha), An Extinct Megafaunal Rodent From The Anguilla Bank, West Indies: Estimates And Implications, Audrone R. Biknevicius, Donald A. Mcfarlane, Ross D. E. Macphee Nov 1993

Body Size In Amblyrhiza Inundata (Rodentia, Caviomorpha), An Extinct Megafaunal Rodent From The Anguilla Bank, West Indies: Estimates And Implications, Audrone R. Biknevicius, Donald A. Mcfarlane, Ross D. E. Macphee

WM Keck Science Faculty Papers

Rodent species typically evolve larger mean body sizes when isolated on islands, but the extinct caviomorph Amblyrhiza inundata, known only from Quaternary cave deposits on the islands of Anguilla and St. Martin (northern Lesser Antilles), provides an unusually dramatic example of insular gigantism. Here we report on a series of body mass estimates for Amblyrhiza using predictive equations based on anteroposterior diameters and cortical cross-sectional areas of humeral and femoral diaphyses. Analyses of 14 isolated specimens (5 femoral, 9 humeral), all representing adult or near adult animals, yield body mass estimates ranging from slightly less than 50 kg to more …


Amblyrhiza And The Vertebrate Paleontology Of Anguillean Caves, Donald A. Mcfarlane, Ross D. E. Macphee Jan 1993

Amblyrhiza And The Vertebrate Paleontology Of Anguillean Caves, Donald A. Mcfarlane, Ross D. E. Macphee

WM Keck Science Faculty Papers

Recorded interest in the caves of Anguilla dates back to the second half of the nineteenth century. The earliest explorations were concerned with the locating phosphatic cave earths, and resulted in the mining of several sites. Incidental to this work, the bones of the largest island rodent ever discovered were collected from Aguillan caves. Whereas the phosphate mining operations were short-lived, the remains of the giant rodent Amblyrhiza have catalyzed a continued interest in the caves of Anguilla. The most recent series of explorations have provided the first adequate documentation of Amhlyrhiza fossil sites, and have started to yield radiometric …


Distribution And Evolution Of Forms And Types Of Sieve-Element Plastids In The Dicotyledons, Dietmar Behnke Jan 1991

Distribution And Evolution Of Forms And Types Of Sieve-Element Plastids In The Dicotyledons, Dietmar Behnke

Aliso: A Journal of Systematic and Floristic Botany

Sieve-element plastids may contain any combination of protein crystals (c), protein filaments (f), and starch grains (s), or none of these. All structurally distinct combinations (=forms) possible (s, cs, cfs, c, cf, fs, f, o) are recorded among the 2100 dicotyledons investigated so far with the transmission electron microscope (representing 381 of more than 460 families described). The six forms that include c and/or f define the P-type and are found in some 620 species, mainly confined to Magnolianae, Caryophyllanae, Vitanae, and Rutanae (Fabales, Linales, Rhizophorales). A detailed family-by-family analysis and quantitative form-by-form comparison suggests that form-Ss plastids give rise …


Steps Toward A Natural System Of The Dicotyledons, Gertrud Dahlgren Jan 1991

Steps Toward A Natural System Of The Dicotyledons, Gertrud Dahlgren

Aliso: A Journal of Systematic and Floristic Botany

Embryological character states are mapped on the diagrams of dicotyledons (G. Dahlgren 1989). The often well-defined pattern of distribution forms a basis for discussing and clarifying phylogenetic relations. It is shown how numerous embryological characters, alone or in combinations, support certain systematic constellations, even if the character states may have arisen independently within a varying number of evolutionary lines. Characters presented are: anther wall formation; tapetum types; cells in pollen grains at dispersal; microsporogenesis; ovule morphology; ovule integuments; endothelium; obturator; parietal tissue; embryo sac formation; antipodal cells; hypostase, embryogeny; polyembryony; endosperm formation; persistence of endosperm; ruminate endosperm; endosperm haustoria; perisperm; …


Chromosome Numbers And Evolution In Anoda And Periptera (Malvaceae), David M. Bates Jan 1987

Chromosome Numbers And Evolution In Anoda And Periptera (Malvaceae), David M. Bates

Aliso: A Journal of Systematic and Floristic Botany

Relationships within and between the principally North American, malvaceous genera Anoda and Periptera are assessed through analysis of chromosomal and hybridization data. Chromosome numbers are reported for ten species of Anoda and one of Periptera, and observations on meiosis in hybrid and non hybrid plants are presented. The results indicate: I) that Anoda and Periptera are closely related and occupy a relatively isolated position in the tribe Malveae, 2) that speciation in Anoda has occurred primarily at the diploid level, n = 15 , although A. crenatiflora is tetraploid and A. cristata includes diploids, tetraploids, and hexapJoids, and 3) that …