scholarly journals Life History of the Funnel-web Spider Agelena limbata: Web Site, Growth, and Reproduction.

1992 ◽  
Vol 41 (1) ◽  
pp. 91-101 ◽  
Author(s):  
Koichi TANAKA
Keyword(s):  
Life History ◽  
Web Site ◽  
Web Spider ◽  
History Of ◽  
Growth And Reproduction

Growth and reproduction of the red alga Rhodomela larix

1986 ◽  
Vol 64 (7) ◽  
pp. 1499-1506 ◽  
Author(s):  
Carla D'Antonio
Keyword(s):  
Life History ◽  
Red Alga ◽  
Oregon Coast ◽  
Perennial Plants ◽  
History Of ◽  
Lower Site ◽  
Intertidal Site ◽  
Observation Period ◽  
Growth And Reproduction

Components of the growth and life history of the red alga Rhodomela larix (Turner) C. Agardh were studied during an 18-month period at a high intertidal and a low intertidal site on the central Oregon coast. Growth was measured by following (i) individually marked upright axes, (ii) clumps of axes thought to represent individual plants, and (iii) large patches of R. larix. Variation in size and growth was common among axes, and portions of some axes were clearly perennial. Plants grew most rapidly in the spring and summer (up to 1.2 mm/day) with a large amount of variation occurring between and within zones and among seasons. Overall, plants at the higher site were shorter and had fewer branches during most of the year than plants at the lower site. Gametophytes were more common in the higher site, while tetrasporophytes predominated at both sites. Reproductive axes were present throughout the observation period, although little recruitment of sexual propagules was seen, implying that populations may be maintained by vegetative perennation of individual plants.

Photoperiod and temperature regulation of the life history of Porphyra columbina (Rhodophyta, Bangiales) from central Chile

1986 ◽  
Vol 64 (9) ◽  
pp. 1867-1872 ◽  
Author(s):  
M. Avila ◽  
B. Santelices ◽  
J. McLachlan
Keyword(s):  
Life History ◽  
Growth Rates ◽  
Temperature Regulation ◽  
Optimum Conditions ◽  
Central Chile ◽  
History Of ◽  
Effects Of Temperature ◽  
Growth And Reproduction

The effects of temperature (10, 15, 20 °C) and photoperiod (8:16, 12:12, 16:8 (hours of light: hours of dark)) on the growth and reproduction of different stages in the life history of Porphyra columbina Montagne were assessed. The conchocelis phase had higher growth rates at 12 h light:12 h dark, 45 μmol m−2 s−1, and 15 °C. Under all the temperatures and photoperiods tested, the conchocelis phase could propagate either by monospores or vegetative fragmentation. Conchosporangia were formed only at 10 °C and 8 h light:16 h dark or at 15 °C and either 8 h light:16 h dark or 12 h light:12 h dark. Long photoperiods inhibited conchosporangia formation at all temperatures tested with the exception of 20 °C and 16 h light:8 h dark, where sporangia was formed once. Conchospores were released when the temperature was decreased (15 to 10 °C) maintaining the photoperiod. Conchospore germination occurred under the three photoperiods and temperatures tested. Growth of juvenile fronds was maximum at 15 °C and either 12 h light:12 h dark or 16 h light:8 h dark. Fronds formed carpospores and spermatia at 15 °C and 16 h light:8 h dark only. With optimum conditions the life history was completed in 60 days. Spermatia had three chromosomes (n = 3).

Age, growth, and reproduction in Hector's dolphins

1991 ◽  
Vol 69 (6) ◽  
pp. 1689-1700 ◽  
Author(s):  
Elisabeth Slooten
Keyword(s):  
Life History ◽  
Body Size ◽  
Sexual Maturity ◽  
Fishing Gear ◽  
Male And Female ◽  
Pulp Cavity ◽  
Traditional Procedure ◽  
History Of ◽  
Growth And Reproduction ◽  
Beach Cast

Data are provided on the reproductive biology and life history of Hector's dolphin, Cephalorhynchus hectori, a species found only in New Zealand waters. Samples were taken from 60 dolphins found beach-cast or killed incidentally in fishing gear. Male and female reproductive tracts were examined macroscopically and histologically, and tooth sections provided an age estimate for each individual. The traditional procedure for preparing dolphin teeth was simplified by using a faster stain and more readily available embedding and sectioning equipment. An important advantage of this method is that it facilitates the cutting of thinner sections, increasing the chances of obtaining a section through the centre of the pulp cavity. Sectioning revealed an open pulp cavity in all the teeth examined. The maximum observed age was 19 years for females and 20 years for males. Females reach a larger body size than males, and are apparently larger than males at any given age. Males appear to reach sexual maturity between 6 and 9 years of age, whereas females give birth to their first calf at 7–9 years of age. Mature males have extremely large testes relative to their body size. The largest male found in this study weighed 41.5 kg, with testes (including epididymides) totalling 1.21 kg.

Experimental life history of Echinostoma cinetorchis

1990 ◽  
Vol 28 (1) ◽  
pp. 39 ◽  
Author(s):  
S H Lee ◽  
J Y Chai ◽  
S T Hong ◽  
W M Sohn
Keyword(s):  
Life History ◽  
History Of
Sign in / Sign up

Export Citation Format

Share Document