https://www.searslab.eeb.ucla.edu/bats daily 0.75 2026-04-02 https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1586555888421-JBYSW74WDJ00YMR7KE68/Saccopteryx+bilineata+NEW_6634-1.jpg Bats https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1587004008354-LGBWYQUB62QQ6IR97Q10/image-asset.jpeg Bats https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1587003711799-XF7C28KJFW901SR11EFQ/bat.png Bats https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1590878463954-2JMT2TVKNJRIT0HKTX0D/IMG_1804+2.JPG Bats https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1590878713154-CLRNFOS7TF71HKG5PVNP/IMG_6279.jpeg Bats https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1590878791595-H2H9G3CRCGYRPGWHG4RM/IMG_7945.JPG Bats https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1590878821786-539Z1O9U1WV357R7MG8K/IMG_20190325_151108.jpg Bats https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1775159518596-6YBTWTQAS8AR65083X5Z/batovary.png Bats - Aging bats have more ovarian reserves For decades, scientists have assumed that ovarian aging is similar across mammals, with a steady loss of follicles over time. Our NIH-funded research findings suggest that bats challenge this pattern. Bats appear to begin with and maintain a much larger ovarian reserve well into adulthood, pointing to biological mechanisms that can slow or reshape reproductive aging. https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1590930158444-Q8CP5RG8OTISE45OIOR2/AJ%252BCS24%252Bopsin.jpg Bats - Bats repeatedly lose color vision Few people are aware that bats have good night AND day vision. Some bats can even see colors thanks to two proteins in their eyes: S-opsin which detects blue/UV light and L-opsin which detects green/red light. Many bats, however, lack S-opsin and cannot distinguish colors. In a large, collaborative NSF-funded project, we found that S-opsin has been lost >12 times in our bat group. https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1590930138364-SSI752KDEFYF8TGS7BNN/bat_skull_CT.jpg Bats - Bat teeth inform evolutionary rules A long-standing question in biology is why some morphologies have frequently evolved, while others – though theoretically possible – seemingly have never evolved. In an NSF-funded project using the diverse teeth of bats as a model system, we identified rules of developmental biases that shaped the morphological diversification of bat molars. https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1591124535374-6RGKWGDGPG1RSZC7HNBN/Global+map_bats2-01.png Bats https://www.searslab.eeb.ucla.edu/news daily 0.75 2026-04-02 https://www.searslab.eeb.ucla.edu/news/pi-sears-interviewed-about-her-research-on-womens-health-and-bats monthly 0.5 2026-04-02 https://www.searslab.eeb.ucla.edu/news/pi-karen-sears-becomes-editor-in-chief-of-the-biological-journal-of-the-linnean-society monthly 0.5 2023-09-06 https://www.searslab.eeb.ucla.edu/news/template monthly 0.5 2023-09-06 https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1606491219503-BZUPAUSM2PGS2YQXQOZ3/rosette.png News - PI Karen Sears elected a Fellow of the AAAS and California Academy of Science The newly elected AAAS Fellows will receive rosette pins in gold and blue, colors symbolizing science and engineering. https://www.searslab.eeb.ucla.edu/opossum daily 0.75 2023-03-20 https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1586280428341-RICFWYEX5GJEBVXRR8RJ/image-asset.jpeg Opossum https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1587097406747-4ECECA9U46AQZUSLFDV6/opposum+on+black_background+with+yellow+2.png Opossum https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1586985230972-M2LNH6NRW9TWM9A98QT6/Erophylla+clean.png Opossum https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1586985230972-M2LNH6NRW9TWM9A98QT6/Erophylla+clean.png Opossum https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1586985230972-M2LNH6NRW9TWM9A98QT6/Erophylla+clean.png Opossum https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1587011813360-HCCOYBBX27D9OMIK7TCB/Gray_Short-tailed_Opossum_area.png Opossum IUCN Red List of Threatened Species, species assessors and the authors of the spatial data. / CC BY-SA (https://creativecommons.org/licenses/by-sa/3.0) https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1587008591328-J93VGZCYM68HXZ284DGL/oppossum2.png Opossum https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1593187752399-KSEQHUORWIIWRE8F8NCH/mono_cleared.jpg Opossum - Mammalian development and aging are linked The universality of aging across mammals has engendered much speculation on its causes. In collaboration, we developed “aging clocks” that use methylation patterns to can estimate age across mammal tissues and species. Digging deeper, clock results also suggest that development and aging are linked in most mammals because of their shared reliance on the same methylation machinery. The only mammal lacking this link appears to be opossum, the “exception that proves the rule.” https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1593186273102-SZ1SQT7J8K1R0QVTSMXK/antiTGFb4.jpg Opossum - Mammal middle ear bones came from the “reptile” jaw The possession of a middle ear with several bones is a key mammalian trait. We linked small changes in genes and cells to the separation of the future middle ear bones from the jaw during opossum development. This suggests that it might have been relatively easy for mammals to re-purpose parts of their jaw to make a middle ear. This finding, and others, support the hypothesis that more than one group of mammals independently evolved a middle ear made up of several bones. https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1593186307740-9M18S0ZZIVY7U7BRVLUR/OpossumSt32_isolectinFLcontrast.jpg Opossum - Opossums respond to thalidomide like humans The drug thalidomide has caused disabilities in thousands of children. However, how thalidomide disrupts development in humans remains unresolved. This is, in part, because thalidomide does not disrupt rodent development. We found that opossum embryos exposed to thalidomide display malformations similar to humans. Our findings suggest that opossums make a good mammalian model for future studies of the impact of thalidomide, and other teratogens, on human development. https://www.searslab.eeb.ucla.edu/welcome daily 1.0 2026-04-02 https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1587090761325-U934N47NBO19IVMVF04D/bat+on+black_background.png Welcome https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1587096977746-2ZUDFTSKDTXW98X59U7X/opposum+on+white_background_with+yellow.png Welcome https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1585870095525-VBVJWTTIHSYKAH8ACA7K/bat_embryo.jpg Welcome https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1586923855948-YTN3QL8OR7COR9V7I7TZ/Opossum-Black.jpg Welcome https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1587138839398-PJHUP09P4UKLW205VQQH/BatSkull-Black.png Welcome https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1586923725316-BQ8P0JASRWQRA1Z1N9V7/Bat-White_2.png Welcome https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1586546770210-C7L467MFD5NJ34EL0ESX/nature.png Welcome https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1586926298383-CPHDKDRPDCFTQF0953KW/American+naturalist.png Welcome https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1586797152581-9KGC6HU8AOTX1CQVECSA/PNAS_black.png Welcome https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1586723022101-GHZS4U8JHUO1CXKJHWRB/Nature_E%26E_black.png Welcome https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1586722493787-9SYRY7XV6NP4MGP04NWI/evolution_black.png Welcome https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1587099003203-0RNIF2LE73CPE066UJ11/image-asset.png Welcome https://www.searslab.eeb.ucla.edu/research daily 0.75 2026-04-02 https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1587097490929-GHOY3Z14FODPW1MD4SJG/skeleton+on+black+with+yellow+2.png Research https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1586985250728-3C1994T6GRQYKCKTXNO5/Erophylla%2Bclean.jpg Research - Establishing the developmental rules that shape the evolution of mammal form We explore why certain mammalian forms have never evolved, while others have evolved again and again. We investigate the structure, character, and dynamics of mammalian development and evolution. Funding: NSF IOS 2017803, NSF IOS 1257873, National Geographic Society, NIH HD050042-01 https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1586995775653-KIGAUKD90KBYK2PG78JU/20190326_192123.jpg Research - Understanding evolutionary radiations in bats We help untangle the biological forces (i.e. genomic, anatomical, and ecological) that help bats adapt to their changing environment. We are researching adaptations in many systems, including sensory systems, teeth, skeletons, and wing membranes. Funding: NSF IOS 2017803, NSF IOS 1257873, NSF DEB 1442142, National Geographic Society, NIH HD050042-01 https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/d83afbed-bc82-4629-a808-f900bf2ac5a1/batovary.png Research - Use of natural mammalian diversity to study issues relevant to women’s health We use “weird” mammal species, including the short-tailed opossum and bats, as model systems. We use these natural mutants to study the links between development and biological aging, as well as other drivers of biological aging, with a special focus on women’s health. Funding: NIH OD OD022988, NIH HD050042, NIH AG098364 https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1586959940832-BGMP9A5O20BJTAZ8VQK8/fossilbat_AMNH.jpg Research - Evo-devo of form We study developmental processes that create new forms across the animal kingdom, and the degree to which these processes contribute to evolution. https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1586733790051-NKDW0FGPICW85Q29RQRV/image-asset.jpeg Research - Evolutionary radiations We explore biological processes that allow mammalian species to diversify in response to environmental conditions. https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1586959827519-ICAX2N8FILC3H4JDP7BX/Monodelphis-domestica_fromSearsLab.jpg Research - Women’s Health We use unique mammals to explore the cellular, molecular, and developmental drivers of human physiology, longevity, and health, with a special focus on women’s health. https://www.searslab.eeb.ucla.edu/publications daily 0.75 2023-09-06 https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1589515590144-ABNN5DMXR1MNQPM4JRO3/Erophylla-2.png Publications https://www.searslab.eeb.ucla.edu/about-us daily 0.75 2026-04-02 https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/07bfc1ee-ed06-48b7-b371-8c623de9e2e3/Sears_2025.jpg About us https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1585941480129-IL4U5JCHXE06THTRPHUO/bats_biteforcestudy.jpg About us https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1585941499206-P1C7UOP9R1CAMLC6M29L/CaveDR_AS.JPG About us https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1585941508659-M697DHDY1N3R97HKUVCL/Mata+de+Platano+Field+Station+%2810%29.JPG About us https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1586735161759-0N56VF2ZTS2VCC5QWGC5/image-asset.jpeg About us https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1585940146587-670G204TIKS1HV9J0TNM/4+May+group+shot+2017_OLD1474.jpg About us https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1585940647794-A0PMIMZGVBLQ8W3VNLUJ/Before+entering+the+ice+house%21_Trinidad_AS.jpg About us https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1585940687829-1ZE28HFIQZQDI63VM272/Beach+%285%29.JPG About us https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1585941614165-I7TNEP7CP6PXJLD2RNJU/IMG_7945.JPG About us https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1586735333534-8KZGTRY18ZTQP4FEZU7P/general+action+DSC_4368.jpg About us https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1585941922981-40SVUVB81AI9QBGP3QHE/group_of_ibio_summerstudentsatField+museum.jpg About us https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1585941933874-IB1NIXIAN2S2NS2Y2N5G/Karen+giving+talk+at+meeting.jpg About us https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1585941946926-G1PXK8L55G5Y163ASEE3/Maier+and+Urban+doing+outreach+at+field+museum.JPG About us https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1586735374705-ISXDAF1L7O8R1Z3A9JSP/Urban+thesis+defense.JPG About us https://www.searslab.eeb.ucla.edu/outreach daily 0.75 2020-04-12 https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1585941922981-40SVUVB81AI9QBGP3QHE/group_of_ibio_summerstudentsatField+museum.jpg Outreach https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1585941922981-40SVUVB81AI9QBGP3QHE/group_of_ibio_summerstudentsatField+museum.jpg Outreach https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1585941933874-IB1NIXIAN2S2NS2Y2N5G/Karen+giving+talk+at+meeting.jpg Outreach https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1585941946926-G1PXK8L55G5Y163ASEE3/Maier+and+Urban+doing+outreach+at+field+museum.JPG Outreach https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1586735374705-ISXDAF1L7O8R1Z3A9JSP/Urban+thesis+defense.JPG Outreach https://www.searslab.eeb.ucla.edu/research-in-action daily 0.75 2020-04-12 https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1585941480129-IL4U5JCHXE06THTRPHUO/bats_biteforcestudy.jpg Research in action https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1585941480129-IL4U5JCHXE06THTRPHUO/bats_biteforcestudy.jpg Research in action https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1585941499206-P1C7UOP9R1CAMLC6M29L/CaveDR_AS.JPG Research in action https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1585941508659-M697DHDY1N3R97HKUVCL/Mata+de+Platano+Field+Station+%2810%29.JPG Research in action https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1586735161759-0N56VF2ZTS2VCC5QWGC5/image-asset.jpeg Research in action https://www.searslab.eeb.ucla.edu/working-together daily 0.75 2020-04-12 https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1585940456546-QD4AT1XYLY348QO5WOQJ/image-asset.jpeg Working together https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1585940456546-QD4AT1XYLY348QO5WOQJ/image-asset.jpeg Working together https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1585940647794-A0PMIMZGVBLQ8W3VNLUJ/Before+entering+the+ice+house%21_Trinidad_AS.jpg Working together https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1585940687829-1ZE28HFIQZQDI63VM272/Beach+%285%29.JPG Working together https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1585941614165-I7TNEP7CP6PXJLD2RNJU/IMG_7945.JPG Working together https://images.squarespace-cdn.com/content/v1/5e756d52cbef7c44bc1b6e78/1586735333534-8KZGTRY18ZTQP4FEZU7P/general+action+DSC_4368.jpg Working together https://www.searslab.eeb.ucla.edu/past-lab-members daily 0.75 2024-09-10