The adaptive significance of paedogenesis in North American species of Ambystoma (Amphibia: Caudata): an hypothesis

1974 ◽  
Vol 52 (3) ◽  
pp. 393-400 ◽  
Author(s):  
W. Gary Sprules
Keyword(s):  
Life History ◽  
North America ◽  
North American ◽  
Genetic Basis ◽  
Temperature Fluctuations ◽  
Adaptive Significance ◽  
Supporting Evidence ◽  
Low Humidity ◽  
Ambystomatid Salamanders ◽  
Harsh Conditions

Paedogenesis in varying degrees is exhibited by many species of North American salamanders, particularly of the genus Ambystoma. On the basis of a consideration of the ecology of these species, it is proposed that paedogenesis is evolutionarily adaptive and the following hypothesis is presented. In most habitats where ambystomatid salamanders occur, they exhibit the typical amphibian life history, consisting of aquatic larvae and terrestrial adults. However, where unusually harsh conditions, such as severe temperature fluctuations, lack of suitable cover or food, and low humidity, exist on land then the adjacent aquatic habitat is more suitable for salamanders provided it is permanent and provided fish are rare or absent. Under these circumstances paedogenesis will evolve because salamanders which spend their whole lives as larvae in the water have an adaptive advantage over those which metamorphose and become primarily terrestrial. Supporting evidence for the hypothesis is based primarily on patterns of similarity in the ecology of paedogenetic species of Ambystoma. It is suggested that paedogenesis is most commonly reported from the western mountains because this area contains more permanent fish-free ponds than any other area of North America. Exceptions to the hypothesis are discussed and some speculation on the genetic basis of paedogenesis is offered.

scholarly journals Life History Implications of Complete and Incomplete Primary Molts in Pelagic Cormorants

The Condor ◽  
2001 ◽  
Vol 103 (3) ◽  
pp. 555-569 ◽  
Author(s):  
Christopher E. Filardi ◽  
Sievert Rohwer
Keyword(s):  
Life History ◽  
North America ◽  
North American ◽  
Northeastern Asia ◽  
Flight Feather ◽  
Historia De Vida

Abstract We describe the rules of primary flight-feather replacement for Pelagic Cormorants (Phalacrocorax pelagicus), and contrast the completeness of primary replacement in individuals from Asia and North America. In adult Pelagic Cormorants primary replacement is stepwise, with multiple waves of molt, each initiated at the innermost primary (P1), proceeding simultaneously toward the tip of the wing. Shugart and Rohwer's (1996) ontogenetic model for generating and maintaining stepwise primary replacement depended upon incomplete molts. In each new episode of molt, waves of primary replacement were thought to be initiated at P1 and at each arrested wave that had failed to replace all old feathers in the preceding molt. Because most adult Pelagic Cormorants from North America completely replace their primaries but maintain stepwise primary molts, the latter assumption must be relaxed. In contrast to the present-day situation in North America, Pelagic Cormorants from northeastern Asia have incomplete molts of their primaries, and may be forced to skip breeding in some years to clear their wings of overworn primaries. Young birds from Asia start the replacement of their juvenile primaries later than North American birds and replace more feathers simultaneously. Implicancias de la Muda Primaria Completa e Incompleta en la Historia de Vida de Phalacrocorax pelagicus Resumen. Describimos las reglas de reemplazo de plumas primarias para Phalacrocorax pelagicus y contrastamos la totalización del reemplazo de primarias entre individuos de Asia y América del Norte. En individuos adultos, el reemplazo de primarias ocurre en varias etapas, con múltiples secuencias de muda cada una iniciada en la primaria más interna (P1), procediendo simultáneamente hacia la punta del ala. El modelo ontogenético de Shugart y Rohwer (1996) para la generación y mantenimiento del reemplazo en etapas de las plumas primarias depende de mudas incompletas. Se pensaba que en cada nuevo episodio de muda las secuencias de reemplazo de primarias eran iniciadas en P1 y en cada punto de interrupción de la muda precedente que hubiera impedido el reemplazo de todas las plumas viejas. Debido a que la mayoría de los individuos adultos de P. pelagicus de Norteamérica reeemplazan completamente sus primarias pero aún lo hacen en etapas, la última suposición debe ser re-evaluada. En contraste con la situación actual en Norteamérica, individuos del noreste de Asia tienen mudas incompletas de sus primarias y pueden verse forzados a no reproducirse en algunos años para despojarse de la presencia de primarias desgastadas. Las aves juveniles de Asia comienzan el reemplazo de sus primarias más tarde y reemplazan más plumas simultáneamente que las aves de Norteamérica.

scholarly journals THE BIOLOGY OF THREE NORTH AMERICAN SPECIES OF MESOVELIA (HEMIPTERA-MESOVELIIDAE).,

1932 ◽  
Vol 64 (4) ◽  
pp. 88-95 ◽  
Author(s):  
Clarence H. Hoffmann
Keyword(s):  
Life History ◽  
North America ◽  
North American ◽  
Life Histories ◽  
Lake Michigan ◽  
Common Species ◽  
North American Species ◽  
The Other

The purpose of this paper is to present what is known at the present time concerning the life histories and habits of the Mesoveliidae, particularly those of three species of the genus Mesovelia Muls. found in North America. Studies on our most common species, Mesovelia mulsanti bisignata Uhler, were carried out in Michigan and Kansas, while biological notes on the other two species were taken in the region of Douglas Lake, Michigan, their only known habitat. Isolated rearings and life history studies of all three species were made at Lawrence, Kansas.

DIPTERA LARVAE ASSOCIATED WITH TREES IN NORTH AMERICA

1976 ◽  
Vol 108 (S100) ◽  
pp. 1-53 ◽  
Author(s):  
H.J. Teskey
Keyword(s):  
Life History ◽  
North America ◽  
North American ◽  
Specific Level ◽  
Diptera Larvae

AbstractThis paper treats of larvae of 45 families of North American Diptera which are associated with dead and living trees. A key and illustrations are provided for identification of 43 families whose larvae are sufficiently well known. Also provided is a description of the larvae of each family, the type of larval–tree association, and wherever possible, notes on the life history and behaviour, and an inventory at generic or specific level of the fauna involved.

Epinotia cinereana (Haworth, 1811) bona sp., a Holarctic tortricid distinct from E. nisella (Clerck, 1759) (Lepidoptera: Tortricidae: Eucosmini) as evidenced by DNA barcodes, morphology and life history

Zootaxa ◽  
2012 ◽  
Vol 3318 (1) ◽  
pp. 1 ◽  
Author(s):  
Marko MUTANEN ◽  
LEIF AARVIK ◽  
JEAN-FRANÇOIS Landry ◽  
ANDREAS H. SEGERER ◽  
OLE KARSHOLT
Keyword(s):  
Life History ◽  
North America ◽  
North American ◽  
Junior Synonym ◽  
Colour Pattern ◽  
Dna Barcodes ◽  
Male And Female ◽  
The North ◽  
The Status ◽  
Morphological Differences

DNA barcodes of European tortricid moths identified as Epinotia nisella (Clerck, 1759) were found to comprise two ge-netically distinct clusters. These coincided with E. nisella and E. cinereana (Haworth, 1811) (sp. rev.), the latter havingbeen considered a synonym of the former for several decades. Comparing these DNA barcodes with those of North Amer-ican Epinotia showed that both species are Holarctic. The North American Proteopteryx criddleana Kearfott, 1907 is anew junior synonym of E. cinereana (syn. nov.). The two species also show distinct differences in male and female gen-italia. North American populations of both species show moderate differences in barcodes from their respective Europeanpopulations but there are no morphological differences correlated with the intraspecific barcode clusters. Tortrix petranaHübner, 1813 is considered as a junior synonym of E. cinereana (syn. rev.). Epinotia nisella has several synonyms reflect-ing its highly variable forewing colour pattern. We discuss its variation and the status of the names associated with it. The biology of both species in Europe and North America is summarized. Adults and genitalia are illustrated.

Lucilia bufonivora, Not Lucilia silvarum (Diptera: Calliphoridae), Causes Myiasis in Anurans in North America With Notes About Lucilia elongata and Lucilia thatuna

2020 ◽  
Author(s):  
T L Whitworth ◽  
Matthew G Bolek ◽  
G Arias-Robledo
Keyword(s):  
Life History ◽  
North America ◽  
North American ◽  
American Studies ◽  
Morphological Differentiation ◽  
Genetic Distances ◽  
Morphological Evidence ◽  
Adult Males ◽  
Adult Females ◽  
Palearctic Region

Abstract In North America, until recently, all cases of anuran myiasis were attributed to Lucilia silvarum (Meigen) or Lucilia elongata Shannon. The latter species is exceedingly rare and its life history is unknown, but L. silvarum is common and was thought to be capable of being either parasitic or saprophytic in North America. Until recently, the anuran parasite Lucilia bufonivora Moniez was thought to be strictly Palearctic, but a study in 2014 has determined this species is established throughout southern Canada. In 2019, a study demonstrated, with molecular and morphological evidence, that two adult flies formerly identified as L. silvarum and reared from amphibian myiasis cases from Canada, are actually L. bufonivora. Although the mentioned study detected relatively high genetic distances with European L. bufonivora, the lack of evident morphological differentiation suggest that they are the same species. The current study examined 12 adult males and eleven adult females morphologically from three additional North American studies. Specimens were examined which had been identified as L. silvarum or L. elongata, and they all proved to be L. bufonivora. We now suspect L. silvarum is strictly saprophagous in North America like they are in the Palearctic Region. We also provide evidence that the pattern of myiasis differs between European and North American specimens.

Experimentally increased costs of parental care are shunted to offspring in species with extended care

2019 ◽  
Author(s):  
Gretchen F. Wagner ◽  
Emeline Mourocq ◽  
Michael Griesser
Keyword(s):  
Life History ◽  
Parental Care ◽  
Total Duration ◽  
Bird Species ◽  
Life History Strategy ◽  
Experimental Treatment ◽  
Cost Of Care ◽  
Adult Survival ◽  
Supporting Evidence ◽  
Trade Offs

Biparental care systems are a valuable model to examine conflict, cooperation, and coordination between unrelated individuals, as the product of the interactions between the parents influences the fitness of both individuals. A common experimental technique for testing coordinated responses to changes in the costs of parental care is to temporarily handicap one parent, inducing a higher cost of providing care. However, dissimilarity in experimental designs of these studies has hindered interspecific comparisons of the patterns of cost distribution between parents and offspring. Here we apply a comparative experimental approach by handicapping a parent at nests of five bird species using the same experimental treatment. In some species, a decrease in care by a handicapped parent was compensated by its partner, while in others the increased costs of care were shunted to the offspring. Parental responses to an increased cost of care primarily depended on the total duration of care that offspring require. However, life history pace (i.e., adult survival and fecundity) did not influence parental decisions when faced with a higher cost of caring. Our study highlights that a greater attention to intergenerational trade-offs is warranted, particularly in species with a large burden of parental care. Moreover, we demonstrate that parental care decisions may be weighed more against physiological workload constraints than against future prospects of reproduction, supporting evidence that avian species may devote comparable amounts of energy into survival, regardless of life history strategy.

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