1,294 research outputs found
Mexican Liberals and the Pueblo Indians, 1821 - 1829
When independence from Spain seemed an irreversible fact and he could no longer avoid acknowledging it, the last Spanish governor of the isolated frontier province of New Mexico, the loyal Facundo Melgares, ordered celebrations in honor of the birth of the new Mexican nation. On 6 January 1822, the streets of Santa Fe rang with the sound of church bells and guns fired into the air, as people made their way to Mass, participated in processions, listened to speeches, watched a special play, and danced well into the night. Among the revelers were Pueblo Indians from Tesuque who performed a splendid dance in the main plaza
Evolution of Sexual Dimorphism and Male Dimorphism in the Expression of Beetle Horns: Phylogenetic Evidence for Modularity, Evolutionary Lability, and Constraint
Beetle horns are enlarged outgrowths of the head or thorax that are used as weapons in contests over access to mates. Horn development is typically confined to males (sexual dimorphism) and often only to the largest males (male dimorphism). Both types of dimorphism result from endocrine threshold mechanisms that coordinate cell proliferation near the end of the larval period. Here, we map the presence/absence of each type of dimorphism onto a recent phylogeny for the genus Onthophagits (Coleoptera: Scarabaeidae) to explore how horn development has changed over time. Our results provide empirical support for several recent predictions regarding the evolutionary lability of developmental thresholds, including uncoupled evolution of alternative phenotypes and repeated fixation of phenotypes. We also report striking evidence of a possible developmental constraint. We show that male dimorphism and sexual dimorphism map together on the phylogeny; whenever small males have horns, females also have horns (and vice versa). We raise the possibility that correlated evolution of these two phenomena results from a shared element in their endocrine regulatory mechanisms rather than a history of common selection pressures. These results illustrate the type of insight that can be gained only from the integration of developmental and evolutionary perspectives
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