New paper: Primary productivity explains size variation across the Pallid bat’s western geographic range

Pallid bat skullWhy do some species have larger individuals in certain parts of their range?  In many animal species, body size tends to increase with latitude. This famous ecological pattern, known as Bergmann’s Rule, was originally thought to be an adaptation for heat conservation. However, several hypotheses have been proposed, such as resource availability, resistance to starvation, and heat dissipation. We evaluate which of these hypotheses best explain geographic size variation in the Pallid bat in our new paper (Kelly et al., in press). We also investigate potential consequences of size variation by testing whether skull shape (an indicator of bite performance) changes in tandem with size.

Our results suggest that primary productivity (a proxy for resource availability) and to a lesser extent, heat conservation, best explain size variation across the Pallid bat’s western range. We also found that larger individuals have cranial traits associated with greater bite force production. This may help explain why larger individuals tend to consume larger and harder prey. Our results suggest that resource availability is a major factor explaining size, morphology, and possibly feeding performance in a wide-ranging and omnivorous bat species.

New paper on the hindlimb membrane musculature of bats

Virtual dissections in ventral view of the calcar-depressor muscle complex of one hindlimb of (a) Myotis californicus, (b) Molossus molossus, and (c) Artibeus jamaicensis.

Ph.D. student Katie Stanchak just published a new paper describing  the variation in the membrane and limb musculature associated with the calcar – a neomorphic skeletal structure found in the hind limbs of most bats. By combining diffusible iodine-based contrast enhanced computed tomography (diceCT) and standard histological techniques, Katie found that the arrangement of the calcar musculature varies among bat species that have different flight ecologies. These results suggest that the calcar may have a functional role in flight maneuverability, an idea that Katie will be testing in later stages of her Dissertation.

Katie’s article has also been featured in the diceCT blog.

More papers! Behavioral correlates of cranial muscle functional morphology

Check out the new issue of the Anatomical Record, co-edited with Adam Hartstone-Rose and Damiano Marchi! It is full of anatomical goodness, and showcases new findings and cutting-edge techniques in the study of muscle functional morphology. This issue contains several papers by Santana lab members:

Curtis A.A. and Santana S.E. 2018. Jaw-dropping: functional variation in the digastric muscle in bats. The Anatomical Record 301: 279–290. PDF

Santana S.E. 2018. Comparative anatomy of bat jaw musculature via Diffusible Iodine-Based Contrast-Enhanced Computed Tomography. The Anatomical Record 301: 267–278. PDF

Hartstone-Rose and Santana S.E. 2018. Behavioral correlates of cranial muscle functional morphology. The Anatomical Record 301: 197–201. PDF

Arbour J.A. and López-Fernández H. 2018. Intrinsic Constraints on the Diversification of Neotropical Cichlid Adductor Mandibulae Size. The Anatomical Record 301: 216–226.


New paper: Auditory opportunity and visual constraint enabled the evolution of echolocation in bats

Why are there bats that do not echolocate, and how has body size and morphology constrained or facilitated the evolution of sensory diversity in bats? In a collaborative paper in Nature Communications, we present a broad phylogenetic comparative analysis that illuminates the trade-offs between vision and echolocation during bat evolution. You can access the open-access paper here. Enjoy!


The evolution of anterior coloration in carnivorans

Why does the spectacled bear have facial stripes? Or why do canids have relatively plain faces? In a new article with the Caro and Stankowich labs, we explored the behavioral factors that might predict the diversity in facial and chest colors in carnivorans. Much to our surprise, we found that there might be different factors associated with the evolution facial and chest coloration in different lineages. Find out more by reading  the full article in Behavioral Ecology and Sociobiology, or its press coverage from Science.

Caro et al. 2017
Caro et al. 2017

NASBR 2017

We travelled to Knoxville for the 2017 North American Symposium for Bat Research! As always, we had a wonderful time presenting and discussing our work, and catching up with our fellow bat biologists. Here are some highlights of the meeting:

Leith Miller presenting her poster on the evolution of noseleaves and ears in phyllostomid bats
Rochelle Kelly presenting her work on San Juan Island bats
Rochelle Kelly presenting her work on San Juan Island bats
Rochelle wins the Titley Electronics award for her presentation!
Abbie presenting her work on the comparative anatomy and function of the jaw-opening muscle of bats
Abbie presenting her work on the comparative anatomy of bats’ jaw-opening muscle
Presenting on the relationship between plant scents and bat diets
Sharlene presenting on the relationship between plant scents and fruit bat diets
A great turnout at the diversity breakfast!
A great turnout at the diversity breakfast!
Latin American friends!
Latin American friends from 7 countries!



New Outreach Project: Pocket Bats!

pocket bats LOGO-01-01fullsizeoutput_14d6Postdocs, Dr. Abigail Curtis and Dr. Jessica Arbor, have just launched a new page on the Santana Lab website for our new and exciting outreach project “Pocket Bats!” Check out 3D augmented reality models of skulls from some of the amazing bats we are studying in the Santana Lab at the University of Washington using a free Augmented Reality app that works on iPhone and Android devices! We have already added five Pocket Bat Cards to the Pocket Bats page, with many more exciting species to come! Link:


Team returns from Costa Rica

Ada and Leith have returned from a successful trip to La Selva Biological Station, Costa Rica! This field trip was part of our project investigating the coevolution between plant chemical signals and frugivorous bats. The team collected  scent samples from fruits, and conducted behavioral experiments to measure what scents bats prefer.  They were joined by our collaborators at the Dávalos and Rossiter labs, who are working on the sensory genomics of tropical bats.

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