Weber State University Department of Zoology

More coverage on Dr. Jung's research.

Only two species can survive in Great Salt Lake? Scientist says — hold my Nalgene Scientist Julie Jung set out on a hike along the Great Salt Lake to find nematodes. She ended up discovering a new species.

New publicity for Dr. Jung's research with colleagues at the U of U!

Great Salt Lake roundworm gets Shoshone name - @theU New study by U biologists characterizes D. woaabi, first of two nematode species recently found in the lake's microbialites.

A few shots from the first week of Freshwater Ecology, 2025.

Assembling the Pecos River fish fauna: barrier displacement on the Southern Great Plains, North America Barrier displacement by river capture is an important mechanism for the assembly of freshwater fish faunas. The production of increasingly comprehensive and rigorously dated phylogentic trees for maj...

Yellowstone National Park is hiring! Most applications close 12/16. Check them our ASAP:

Work With Us - Yellowstone National Park (U.S. National Park Service) Youth Conservation Corps

My recently published collaboration with colleagues from Chiapas has made the fish news 🙂

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 México 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."

𝗥𝗲𝘀𝗲𝗮𝗿𝗰𝗵 𝗧𝗶𝘁𝗹𝗲
Historical biogeography of North American killifishes (Cyprinodontiformes) recapitulates geographical history in the Gulf of México watershed

𝗖𝗶𝘁𝗮𝘁𝗶𝗼𝗻
Sonia Gabriela Hernández-Ávila, Christopher W Hoagstrom, Wilfredo A Matamoros, Historical biogeography of North American killifishes (Cyprinodontiformes) recapitulates geographical history in the Gulf of México watershed, Zoological Journal of the Linnean Society, Volume 202, Issue 2, October 2024, zlae105, https://doi.org/10.1093/zoolinnean/zlae105

𝗔𝗯𝘀𝘁𝗿𝗮𝗰𝘁
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 México 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.

𝗣𝗵𝗼𝘁𝗼 𝗖𝗿𝗲𝗱𝗶𝘁
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

Zoology majors are representing in full force at the joint meeting of the Association of Field Ornithologists, Society of Canadian Ornithology, and Wilson Ornithological Society in Peoria, IL this week. Dr. Cavitt and his crew left WSU last week and undertook an epic birding road trip ending in Peoria, IL. All students presented their research today and did a fantastic job! Even ran into Dr Brasso who was also in attendance… was well represented in the ornithological research community today!

Lovely morning on Strongs Creek, collecting invertebrates with Quinlan and Zoe! Dr. Rebecka Brasso and students will sample them for mercury content.