Reproductive Morphology of the Anchialine Shrimp Procaris ascensionis (Decapoda: Procarididae)

1988 ◽  
Vol 8 (3) ◽  
pp. 333 ◽  
Author(s):  
Bruce E. Felgenhauer ◽  
Lawrence G. Abele ◽  
Won Kim
Keyword(s):  
Reproductive Morphology

scholarly journals Male sexual ornament size is positively associated with reproductive morphology and enhanced fertility in the stalk-eyed fly Teleopsis dalmanni

2008 ◽  
Vol 8 (1) ◽  
pp. 236 ◽  
Author(s):  
David W Rogers ◽  
Matthew Denniff ◽  
Tracey Chapman ◽  
Kevin Fowler ◽  
Andrew Pomiankowski
Keyword(s):  
Reproductive Morphology ◽  
Sexual Ornament

Mesocyparis borealis gen. et sp. nov.: fossil Cupressaceae from the early Tertiary of Saskatchewan, Canada

1987 ◽  
Vol 65 (11) ◽  
pp. 2338-2351 ◽  
Author(s):  
E. E. McIver ◽  
J. F. Basinger
Keyword(s):  
Northern Hemisphere ◽  
Branching Pattern ◽  
Natural Group ◽  
Classification Schemes ◽  
Cone Structure ◽  
Reproductive Morphology ◽  
Extant Genus ◽  
Early Tertiary ◽  
Seed Cone ◽  
First Time

Fossil cedar foliage of the Cupressinocladus interruptus type, with associated seeds and cones, is locally abundant in Paleocene deposits of the Ravenscrag Formation, southwestern Saskatchewan, Canada. Vegetative remains of this type occur frequently in early Tertiary plant assemblages throughout the northern hemisphere, indicating that this now extinct cedar was once widespread. For the first time this cedar can be described on the basis of both vegetative and reproductive morphology. Foliage is frond-like with a characteristic opposite branching pattern. Seed cones are globose and woody and bear four equal and decussate scales with prominent umbos. Seeds bear large, equal, semicircular wings. The fossil cedar appears most closely related to extant Cupressaceae such as Thuja, Chamaecyparis, and Heyderia. Foliage closely resembles that of Thuja, while cones are most similar to those of Chamaecyparis. The fossil differs sufficiently in foliage and seed cone structure to preclude assignment to an extant genus and is here assigned to Mesocyparis borealis gen. et sp. nov. Similarities among such extant genera as Thuja, Chamaecyparis, Heyderia, and Thujopsis and the fossil Mesocyparis borealis suggest that all may belong to a single natural group. Furthermore, this group may be more closely related to the southern hemispheric genera Libocedrus, Papuacedrus, and Austrocedrus than present classification schemes imply. Our examination of the Cupressaceae indicates that a revision of present systems of classification is required to accommodate evidence from both extant and extinct cedars.

scholarly journals Effect of competitive cues on reproductive morphology and behavioral plasticity in male fruitflies

2015 ◽  
Vol 27 (2) ◽  
pp. 452-461 ◽  
Author(s):  
Amanda Bretman ◽  
Claudia Fricke ◽  
James D. Westmancoat ◽  
Tracey Chapman
Keyword(s):  
Behavioral Plasticity ◽  
Reproductive Morphology

Thermoregulation, growth, and reproduction in Alaskan collared lemmings: role of short day and cold

1991 ◽  
Vol 261 (3) ◽  
pp. R522-R530 ◽  
Author(s):  
H. A. Maier ◽  
D. D. Feist
Keyword(s):  
Food Intake ◽  
Thermal Conductance ◽  
Reproductive Condition ◽  
Reproductive Morphology ◽  
Short Day ◽  
Long Day ◽  
Dicrostonyx Groenlandicus ◽  
Before And After ◽  
Growth And Reproduction

To assess factors controlling seasonal thermoregulatory and reproductive changes, collared lemmings (Dicrostonyx groenlandicus) were exposed for 16 wk to long day (LD, 22 h light: 2 h dark) and warm (15 +/- 3 degrees C), LD and cold (1 +/- 0.5 degrees C), short day (SD, 4 h light: 20 h dark) and warm, SD and cold or acclimatized to outdoor winter conditions (OUT). Hair length and color, body mass, and food intake were monitored weekly. Resting metabolic rates (RMR) and nonshivering thermogenesis (NST) were estimated several times by measuring oxygen consumption before and after norepinephrine injections. Body composition and reproductive condition were determined at the end of the experiment. SD and OUT groups had a 15.8% lower (P less than 0.01) RMR at 7 degrees C than the LD groups. Lower thermal conductance in SD and OUT animals appears due to molt to white winter pelage, which occurred by week 3 in SD but not in LD groups. Neither SD, cold, nor OUT altered NST or reproductive morphology. SD-exposed lemmings showed 19.2% greater growth than those in LD, resulting primarily from a 29.2 and 15.0% increase in lean and ash components, respectively. Cold exposure increased food intake by 34.7%. Results suggest that the pineal gland, which mediates SD effects, may influence molt and growth but not NST or reproductive morphology.

Male and female reproductive morphology in the inseminating genus Astroblepus (Ostariophysi: Siluriformes: Astroblepidae)

2012 ◽  
Vol 251 (1) ◽  
pp. 38-48 ◽  
Author(s):  
Maria Angélica Spadella ◽  
Claudio Oliveira ◽  
Hernán Ortega ◽  
Irani Quagio-Grassiotto ◽  
John R. Burns
Keyword(s):  
Male And Female ◽  
Reproductive Morphology
Sign in / Sign up

Export Citation Format

Share Document