scholarly journals Life history of the Critically Endangered largetooth sawfish: a compilation of data for population assessment and demographic modelling

2020 ◽  
Author(s):  
PM Kyne ◽  
M Oetinger ◽  
MI Grant ◽  
P Feutry
Keyword(s):  
Life History ◽  
Critically Endangered ◽  
Population Assessment ◽  
History Of ◽  
Demographic Modelling

scholarly journals Carex secalina (Cyperaceae), a species critically endangered in Europe: from propagule germination to propagule production

2011 ◽  
Vol 74 (2) ◽  
pp. 141-147 ◽  
Author(s):  
Waldemar Żukowski ◽  
Marlena Lembicz ◽  
Paweł Olejniczak ◽  
Agnieszka Bogdanowicz ◽  
Julian Chmiel
Keyword(s):  
Life History ◽  
Small Area ◽  
Critically Endangered ◽  
Age At First Reproduction ◽  
The Third ◽  
Germination Ability ◽  
First Reproduction ◽  
History Of ◽  
Selected Traits ◽  
And Bisexual

The size and reproduction ability of the three field populations of <em>Carex secalina</em> Willd. ex Wahlenb. have been assessed. In the parallel garden study selected traits from the life history of the species have been studied, such as age at first reproduction, fertility, the size of seeds, their germination ability and size of seedlings. The populations of <em>C. secalina</em> discovered in Poland in 2000 are characterised by small abundance and small area. All individuals from the three populations in the garden produced generative shoots in the third year of life. Statistically significant differences between the populations were found in the production of shoots with unisexual spikes and bisexual ones, the latter had not been reported in the hitherto literature on the species. The seeds started germinating after a 6-months rest. The first seedlings were observed in the first decade of May. The largest seedlings were noted in the population producing the smallest seeds. The results contribute to explaining the renewal of the populations of this species in the field.

scholarly journals Sawfish, Read in Tooth and Saw: rostral teeth as endogenous chemical records of movement and life-history in a critically endangered species

2019 ◽  
Author(s):  
Jens C. Hegg ◽  
Breanna Graves ◽  
Chris M. Fisher
Keyword(s):  
Life History ◽  
Endangered Species ◽  
Critically Endangered ◽  
Historical Sources ◽  
Continuous Growth ◽  
Chemical Tracers ◽  
Critically Endangered Species ◽  
Salinity Gradients ◽  
Archived Samples ◽  
History Of

AbstractThe ecology of endangered and rare species can be difficult to study due to their low abundances and legal limits on scientist’s ability to catch, sample, and track them. This is particularly true of sawfish (family Pristidae) whose numbers have declined precipitously, placing all five species on the CITES list of critically endangered species worldwide. Best known for their distinctive, toothed rostrum the ecology, movement, and life-history of sawfish is poorly understood. Sawfish rostral teeth are modified placoid scales, which grow continuously throughout the life of the fish. This continuous growth, combined with their stable calcified makeup, makes sawfish teeth a potential source of temporal records of chemical and isotopic changes through the life of the fish. Rostral teeth can be removed non-lethally from living animals and are also often preserved in rostra housed in museums and as curios, potentially allowing both contemporaneous and historical sources of life-history data. Study of the potential for sawfish rostral teeth as endogenous chemical and structural records is extremely limited, however. Using archived samples of largetooth sawfish (Pristis pristis) we show that multiple chemical tracers can be recovered from sawfish teeth, and that these tracers can be used to understand movement across salinity gradients and between freshwater and the ocean. We further show that sawfish teeth contain repeated structures and indistinct banding which could potentially be used for aging or growth analysis of fish.

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

Queering Gender Identity Work: A Life History of a Black Transgender Woman

2018 ◽  
Vol 5 (1) ◽  
Author(s):  
Esethu Monakali
Keyword(s):  
Life History ◽  
Gender Identity ◽  
Public Spaces ◽  
Identity Work ◽  
Social Identities ◽  
Gender And Sexuality ◽  
Ongoing Effort ◽  
History Of ◽  
The Individual

This article offers an analysis of the identity work of a black transgender woman through life history research. Identity work pertains to the ongoing effort of authoring oneself and positions the individual as the agent; not a passive recipient of identity scripts. The findings draw from three life history interviews. Using thematic analysis, the following themes emerge: institutionalisation of gender norms; gender and sexuality unintelligibility; transitioning and passing; and lastly, gender expression and public spaces. The discussion follows from a poststructuralist conception of identity, which frames identity as fluid and as being continually established. The study contends that identity work is a complex and fragmented process, which is shaped by other social identities. To that end, the study also acknowledges the role of collective agency in shaping gender identity.

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