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Record W1915575078 · doi:10.1163/193724012x626458

A molecular dissection of the mating system of the Dungeness crab, Metacarcinus magister (Brachyura: Cancridae)

2012· article· en· W1915575078 on OpenAlex

Why this work is in the frame

A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.

affAt least one author lists a Canadian institution in the pinned OpenAlex snapshot.

Bibliographic record

VenueJournal of Crustacean Biology · 2012
Typearticle
Languageen
FieldEnvironmental Science
TopicCrustacean biology and ecology
Canadian institutionsDalhousie University
Fundersnot available
KeywordsSpermathecaBiologySpermSperm competitionHuman fertilizationZoologyMatingFemale sperm storageInseminationAndrologyAnatomyBotany

Abstract

fetched live from OpenAlex

Microsatellites were used to determine paternity of Metacarcinus magister (Dana 1852), the Dungeness crab, embryos produced through controlled laboratory matings. Additionally, spermathecal and bursal sperm from mated females were genotyped to elucidate patterns of sperm storage and use. Spermathecal and bursal contents and egg clutches from female M. magister of unknown mating history were similarly analyzed. Genotyping of embryos revealed that bursal sperm are not used in fertilization. Multiple paternity was discovered in clutches from controlled matings and in 40% of clutches carried by crabs of unknown mating history. Males achieve last male sperm precedence through stratification of ejaculates within the spermatheca, but males may actually reduce their reproductive success by depositing too much sperm in the spermatheca. Stratification occasionally fails if the fresh ejaculate is large in volume, or when large volumes of stored sperm are present in the spermatheca, resulting in displacement of stored sperm towards the oviduct and multiple paternity within clutches. Sperm competition is interannual between the single primary male mate at each molt (adult females molt and mate once a year and sperm is retained across molts), and clutches fertilized with sperm as old as 2.5 years can develop to maturity. Female crabs may copulate for reasons other than to gain sperm for fertilization. Despite possessing internal sperm storage organs where oöcytes first encounter sperm, the act of fertilization in M. magister may occur externally.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.

Full frame distilled prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.

metaresearch head score (Codex)0.001
metaresearch head score (Gemma)0.000
Version: codex-gemma-dda1882f352aValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Observational · Consensus signal: Observational
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.091
Threshold uncertainty score0.316

Codex and Gemma teacher scores by category

CategoryCodexGemma
Metaresearch0.0010.000
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0000.000
Bibliometrics0.0000.000
Science and technology studies0.0000.001
Scholarly communication0.0000.000
Open science0.0010.000
Research integrity0.0000.000
Insufficient payload (model declined to judge)0.0000.000

Machine scores (provisional)

The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.

Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.

Opus teacher head0.010
GPT teacher head0.230
Teacher spread0.221 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it