Possible genetic reproductive isolation between two tilapiine genera\nand species: Oreochromis niloticus and Sarotherodon melanotheron
Bibliographic record
Abstract
Successful crossbreeding between Oreochromis niloticus\t and\nSarotherodon melanotheron to produce a commercial hybrid has been\ndifficult. The karyotypes and isoenzyme of these two species and their\nreciprocal hybrids (O. niloticus ♀ × S. melanotheron\n♂, S. melanotheron ♀ × O. niloticus ♂, the last\nnot included in the isoenzyme study) were investigated via metaphase\nchromosomes obtained from head kidney cells and electropherogram of\nlactate dehydrogenase (LDH) isoenzymes from the liver, kidney, white\nmuscle, heart, and eye balls. The diploid chromosome number (2n=44) and\nthe fundamental number (NF=50) of the four tilapia genotypes were the\nsame. However, the karyotype of O. niloticus had three pairs of\nsub-metacentric (sm), twelve pairs of sub-telocentric (st), and seven\npairs of telocentric (t) chromosomes, while S. melanotheron had one\npair of metacentric (m), two pairs of sm, 12 pairs of st, and seven\npairs of t chromosomes. The reciprocal hybrids both showed a mixed\nkaryotype range between their parents: 0.5 pair of m, 2.5 pairs of sm,\n12 pairs of st, and seven pairs of t chromosomes. In view of the\nelectropherogram of isozymes, only the LDH of the kidney showed\nsignificant clear bands, with five bands in O. niloticus, three bands\nin S. melanotheron, and duplicated six bands in the hybrids. The bands\nvaried depending on their activities and mobilities. We considered that\nthe differences in karyotype and isoenzyme were related to the genetic\nmechanism for post-mating isolation, and provided some additional basic\ngenetic background of their taxonomy.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot 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.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.003 | 0.000 |
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.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".