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PremisePhylogenetic trees of bryophytes provide important evolutionary context for land plants. However, published inferences of overall embryophyte relationships vary considerably. We performed phylogenomic analyses of bryophytes and relatives using both mitochondrial and plastid gene sets, and investigated bryophyte plastome evolution. MethodsWe employed diverse likelihood‐based analyses to infer large‐scale bryophyte phylogeny for mitochondrial and plastid data sets. We tested for changes in purifying selection in plastid genes of a mycoheterotrophic liverwort (Aneura mirabilis) and a putatively mycoheterotrophic moss (Buxbaumia), and compared 15 bryophyte plastomes for major structural rearrangements. ResultsOverall land‐plant relationships conflict across analyses, generally weakly. However, an underlying (unrooted) four‐taxon tree is consistent across most analyses and published studies. Despite gene coverage patchiness, relationships within mosses, liverworts, and hornworts are largely congruent with previous studies, with plastid results generally better supported. Exclusion ofRNAedit sites restores cases of unexpected non‐monophyly to monophyly forTakakiaand two hornwort genera. Relaxed purifying selection affects multiple plastid genes in mycoheterotrophicAneurabut notBuxbaumia. Plastid genome structure is nearly invariant across bryophytes, but thetufA locus, presumed lost in embryophytes, is unexpectedly retained in several mosses. ConclusionsA common unrooted tree underlies embryophyte phylogeny, [(liverworts, mosses), (hornworts, vascular plants)]; rooting inconsistency across studies likely reflects substantial distance to algal outgroups. Analyses combining genomic and transcriptomic data may be misled locally for heavilyRNA‐edited taxa. TheBuxbaumiaplastome lacks hallmarks of relaxed selection found in mycoheterotrophicAneura. Autotrophic bryophyte plastomes, includingBuxbaumia, hardly vary in overall structure.
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Evidence of endozoochory in upland geese Chloephaga picta and white‐bellied seedsnipes Attagis malouinus in sub‐Antarctic Chile
Abstract Birds are known to act as potential vectors for the exogenous dispersal of bryophyte diaspores. Given the totipotency of vegetative tissue of many bryophytes, birds could also contribute to endozoochorous bryophyte dispersal. Research has shown that fecal samples of the upland goose (Chloephaga picta) and white‐bellied seedsnipe (Attagis malouinus) contain bryophyte fragments. Although few fragments from bird feces have been known to regenerate, the evidence for the viability of diaspores following passage through the bird intestinal tract remains ambiguous. We evaluated the role of endozoochory in these same herbivorous and sympatric bird species in sub‐Antarctic Chile. We hypothesized that fragments of bryophyte gametophytes retrieved from their feces are viable and capable of regenerating new plant tissue. Eleven feces disk samples containing undetermined moss fragments fromC. picta(N = 6) andA. malouinus(N = 5) and six moss fragment samples from wild‐collected mosses (Conostomumtetragonum,Syntrichiarobusta, andPolytrichumstrictum) were grown ex situ in peat soil and in vitro using a agar Gamborg medium. After 91 days, 20% of fragments fromA. malouinusfeces, 50% of fragments fromC. pictafeces, and 67% of propagules from wild mosses produced new growth. The fact that moss diaspores remained viable and can regenerate under experimental conditions following the passage through the intestinal tracts of these robust fliers and altitudinal and latitudinal migrants suggests that sub‐Antarctic birds might play a role in bryophyte dispersal. This relationship may have important implications in the way bryophytes disperse and colonize habitats facing climate change.
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- Award ID(s):
- 1658651
- PAR ID:
- 10449184
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Ecology and Evolution
- Volume:
- 11
- Issue:
- 14
- ISSN:
- 2045-7758
- Page Range / eLocation ID:
- p. 9191-9197
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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