10/29/2024
My recently published collaboration with colleagues from Chiapas has made the fish news ๐
New research looks at North American killifishes exceptional ability to disperse and populate new habitats. Focusing on five families to collectively illustrate how a tolerant, explorative lineage, surviving >50 million years can exploit rare opportunities for range expansions and niche shifts, leading to lineage branching and sustained or even accelerated diversification.
Paywall - https://academic.oup.com/zoolinnean/article-abstract/202/2/zlae105/7845214
"Over 50 Myr, the Gulf of Meฬxico and its tributary drainages have offered many such opportunities. Furthermore, killifish populations can be tremendously persistent, as evidenced by numerous relict taxa. Not only have North American killifishes diversified dramatically since the Eocene, writing their own version of the history of the Gulf in their phylogeny, but many disjunct and disparate populations have survived to the present, living their legacies for us to discern, appreciate, and study."
๐ฅ๐ฒ๐๐ฒ๐ฎ๐ฟ๐ฐ๐ต ๐ง๐ถ๐๐น๐ฒ
Historical biogeography of North American killifishes (Cyprinodontiformes) recapitulates geographical history in the Gulf of Mรฉxico watershed
๐๐ถ๐๐ฎ๐๐ถ๐ผ๐ป
Sonia Gabriela Hernรกndez-รvila, Christopher W Hoagstrom, Wilfredo A Matamoros, Historical biogeography of North American killifishes (Cyprinodontiformes) recapitulates geographical history in the Gulf of Mรฉxico watershed, Zoological Journal of the Linnean Society, Volume 202, Issue 2, October 2024, zlae105, https://doi.org/10.1093/zoolinnean/zlae105
๐๐ฏ๐๐๐ฟ๐ฎ๐ฐ๐
We analysed phylogenetic relationships within a major clade of Cyprinodontiformes (Teleostei) that includes five families of North American killifishes.
We used DNA sequences from five genes for 130 species, with four fossil calibrations and three secondary calibrations, to generate a time-calibrated phylogeny. We estimated diversification rates, ancestral areas, and ancestral habitats for each node. Findings were interpreted within a detailed biogeographical synthesis. The results indicate that the clade arose in the Eocene along the Gulf of Mรฉxico coast. The speciation rate was uniform through time, except for acceleration in Cyprinodontidae after ~10.9 Mya. In other families, neither viviparity nor marine-to-freshwater transition was associated with accelerated speciation. Sea-level fluctuations might have created a speciation pump by stimulating cycles of dispersal and vicariance along the coast. Diversification also included many cases of inland immigration from coastal ancestors. For upland lineages, ancient river drainages accord with lineage distributions, including enigmatic disjunctions in Goodeidae and Fundulus. Diversification in uplands occurred via barrier displacement within alluvial or tectonically active landscapes.
Killifishes also display high environmental tolerance and persist within harsh, peripheral environments unsuitable for most other fishes. Hence, a combination of clade antiquity, adaptability, dynamic geography, and persistence can explain the living diversity of New World killifishes.
๐ฃ๐ต๐ผ๐๐ผ ๐๐ฟ๐ฒ๐ฑ๐ถ๐
Left - Phylogenetic relationships and divergence times among taxa within North American killifish families Cubanichthyidae, Cyprinodontidae, Fundulidae, Goodeidae, and Profundulidae recovered by Bayesian inference with five concatenated loci (three mitochondrial and two nuclear) and 130 species. Red dots depict nodes with posterior probabilities
