New Species Tree Sampling Design Study

Rebecca Harris has a new paper in the journal Evolution on the influence of sampling design on species tree inference. The paper also has a new phylogeny for New World Chickadees.

Link to article.

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Road Cruising Washington: Africa Edition

Savannah monitor from Bellingham.

Savannah monitor from Bellingham. Courtesy Jess Hackler.

Road cruising for reptiles in Washington just got a lot more interesting. This savannah monitor lizard (Varanus exanthematicus) was found over the weekend in Bellingham merging onto Interstate 5 at the Lakeway Exit 253 on-ramp. The species is typically found in arid regions of Africa, not the Pacific Northwest. The lizard probably rafted across the Atlantic Ocean on a log, and then trekked across North America before giving up on circumnavigating the globe when it encountered the Pacific Ocean. The species is also popular in the pet trade.

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Rocket Frog

This photo was taken by NASA during a launch on September 6, 2013 from the Wallops/Mid-Atlantic Regional Spaceport.

Apparently, the launchpad has a pool for the high-volume water deluge system that activates during launches to protect the pad from damage and for noise suppression. This might be a nice spot for a frog to hang out, or this is a terrestrial toad that was just caught in the wrong place at the wrong time. Full story.

Rocket frog launch at Wallops Island Flight Facility in Virginia on September 6, 2013. Credit NASA/Wallops/Mid-Atlantic Regional Spaceport.

Rocket frog launch at Wallops Island Flight Facility in Virginia on September 6, 2013. Credit NASA/Wallops/Mid-Atlantic Regional Spaceport.

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Species Trees and Gene Flow

Our new paper on the impacts of gene flow on species tree estimation is in press at Systematic Biology. Gene flow can cause gene trees to conflict with one another, and therefore we typically try to shelter our species tree analyses from anything other than incomplete lineage sorting. What happens if some gene flow sneaks into the analysis?
We use simulations to characterize estimation errors that result from various models of gene flow. Even in cases where the topology of the species tree is estimated with high accuracy, we find that gene flow can still result in overestimates of population sizes (species tree dilation) and underestimates of divergence times (species tree compression).
Species tree distortion is illustrated below using species trees and Homer Simpson.

Figure 1. Species tree distortions caused by gene flow. Dashed lines illustrate species tree (and Homer) compression, and the widening of branches (and Homer) illustrates species tree dilation.

Figure 1. Species tree distortions caused by gene flow. Dashed lines illustrate species tree (and Homer) compression, and the widening of branches (and Homer) illustrates species tree dilation.

Leaché, A. D., R. B. Harris, B. Rannala, and Z. Yang. The influence of gene flow on species tree estimation: A simulation study. Systematic Biology, In Press.

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2013 Summer Fashion Trends: Taxonomy Edition

Picking the perfect t-shirt to showcase your taxonomic proclivities is an extremely important decision. With so many different options out there, choosing the one to best-fit your personal biases can be an intimidating and difficult decision. Some aspects to consider are fabric quality, t-shirt fit, sizing and colors. I scored this epic t-shirt at the annual herpetology meetings in Albuquerque. The shirt is a must-have for anyone that has blind hatred for any and all taxonomic changes in squamate phylogeny.

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Back.

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Front.

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