Two peer-reviewed species studies close long questions
A carnivorous alpine Saxifraga in China and an extinct toad from La Brea close long-open species and carnivory questions in peer-reviewed work built on multi-line evidence.
Science··Midday
Saxifraga candelabrum emerges as carnivorous on four evidence lines
A peer-reviewed study published in Nature Communications on 4 August reports that Saxifraga candelabrum, an alpine plant of China's mountain forests, catches insects on glandular hairs, produces digestive enzymes and takes up nitrogen from its prey. The study grounds carnivory in four separate evidence lines. Field experiments and herbarium surveys establish capture, enzyme assays establish digestion, and experiments with ¹⁵N-labelled insects establish the transfer of nitrogen into plant tissue. Capture, digestion and nutrient transfer are therefore set out as separate lines for the same plant. A genome comparison finds significant convergence in genes for leaf morphogenesis, digestion and nutrition across six independent origins of carnivory in flowering plants. The authors say the result answers Charles Darwin's long-standing hypothesis that some Saxifraga species might be carnivorous, and that carnivory may be more widespread among angiosperms than assumed. For a living alpine Saxifraga, carnivory becomes concrete when field, laboratory and genomic lines are read together. Those four lines gather, in one agenda, how the plant holds prey, breaks it down and takes nutrients from it.[1]
Spea labreae and a Rhinophrynus find from La Brea
The Natural History Museum of Los Angeles County announced on 5 August that it has described a new extinct amphibian, Spea labreae, in a peer-reviewed paper in the Journal of Vertebrate Paleontology. The holotype is an incomplete sacro-urostyle, the bone where the spine meets the hips, alongside vertebral material that may belong to juveniles. Alberto Cruz compared amphibian bones left unstudied for about 30 years with 80 modern specimens from the museum and from UC Berkeley's Museum of Vertebrate Zoology. The comparison both names the species and tests morphological distinction against modern specimens. The museum says this is the second extinct Pleistocene amphibian described in North America. The same work also yields the first southwestern US find of the genus Rhinophrynus, whose living populations sit in southern Mexico more than 2,400 kilometres away. Material from the La Brea tar pits therefore gathers both a new Ice Age toad and a range-extending genus find in one announcement. The species name and holotype description show how long-untouched collection material can be read through modern comparison.[2]
A living plant and an extinct toad in one species file
The two reports show peer-reviewed species studies closing long-open classification and feeding questions with multi-line evidence, across different organism groups and different time depths. On one side, a living alpine Saxifraga answers Charles Darwin's carnivory hypothesis for the genus through capture, enzyme, nitrogen-transfer and genomic-convergence lines. On the other, bones that waited about 30 years at La Brea yield Spea labreae through modern comparisons and carry the genus Rhinophrynus into the southwestern United States. Both developments rest on peer-reviewed publications summarised in the coverage: one in Nature Communications on 4 August, the other through a 5 August announcement tied to the Journal of Vertebrate Paleontology. What they share is the rebuilding of old questions of species identity and carnivory by using field, laboratory, museum-collection and comparative-morphology lines together. The science desk places the two concrete species files—one living plant, one extinct amphibian—side by side in the same agenda. One recounts how carnivory is established in a living Saxifraga; the other recounts how Ice Age fauna widens with a toad species and a genus range. Neither stops at a single announcement sentence; each lays out evidence lines in an order a reader can follow.[1], [2]
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