About

Harris Lewin is a Distinguished Professor in Evolution and Ecology at the University of California, Davis. He holds the Robert and Rosabel Osborne Endowed Chair in Evolution and Ecology and is affiliated with the Genome Center. His research focuses on evolution and ecology, contributing to the understanding of biological processes through his academic and scientific work. He is based in the College of Biological Sciences at UC Davis, where he is actively involved in teaching, research, and departmental leadership.

Research topics

• Biology
• Evolutionary biology
• Genetics
• Computational biology
• Ecology
• Virology
• Medicine
• Political Science
• Computer Science
• Engineering
• Environmental ethics
• Environmental science
• Zoology
• Mathematics
• Public relations
• Environmental resource management

Selected publications

• Introduction

  Annual Review of Animal Biosciences · 2026-02-18

  articleSenior author
  PublisherDOI

• Side-necked turtle genomes reveal chromosomal dynamics, skeletal innovation and cancer resistance

  bioRxiv (Cold Spring Harbor Laboratory) · 2026-03-07

  articleOpen access

  Turtles exhibit a highly derived body plan, exceptional longevity, cancer resistance, and striking diversity in karyotypes and sex determination systems. However, the genomic basis of these innovations remains unresolved, largely because reference genomes were lacking for one of two extant turtle clades, the side-necked turtles (Pleurodira). As part of the Vertebrate Genomes Project, we generated seven reference-quality Pleurodira genomes and reconstructed the most comprehensive genome-wide turtle phylogeny. Combining demographic inference with historical climate and biome reconstructions indicates that ancient climate fluctuations shaped long-term population dynamics, while recent declines mainly reflect population structure.Ancestral genome reconstructions reveal that rare bursts of chromosome fusions and fissions, likely facilitated by repetitive elements, drove turtle karyotype diversity. By identifying sex chromosomes and tracing their evolutionary history, we resolve a long-standing debate and demonstrate a single origin of genetic sex determination in Chelidae on a microchromosome over 80 million years ago. Contrary to previous hypotheses, we find no evidence of coevolution between genetic sex determination and chromosome number in turtles. Comparative genomic analyses further identify gene losses and signatures of adaptive evolution associated with key turtle traits. Gene losses causing disproportionate dwarfism phenotypes may have contributed to skeletal adaptations underlying the compact turtle body plan. In addition, gene losses and adaptive changes in stress response and tumor suppressor pathways likely enhance oxidative stress tolerance and cancer resistance. Together, these findings illuminate turtle genome evolution, revealing chromosomal dynamics, sex chromosome evolution, molecular insights into skeletal innovation and cancer resistance, and implicate gene losses as a recurrent contributor to evolutionary novelty.

  PublisherOA PDFDOI

• Nine changes needed to deliver a radical transformation in biodiversity measurement

  2025-09-24

  articleOpen access

  Biodiversity is declining in many parts of the world. Biological diversity measurement and monitoring are fundamental to the assessment of the causes and consequences of environmental changes, identification of key areas for the protection of biodiversity or ecosystem services, determining the effectiveness of actions, and the creation of decision-support tools critical to maintaining a sustainable planet. Biodiversity measurement is rapidly changing due to advances in citizen science, image recognition, acoustic monitoring, environmental DNA, genomics, remote sensing and artificial intelligence. In this perspective, we outline the exciting opportunities these developments offer but also consider the challenges. Our key recommendations are to (1) Capitalize on the ability of novel technology to integrate data sources (2) agree to standard methods for data collection (3) ensure new technologies are calibrated with existing data; (4) fill data gaps by using emerging technologies and increasing capacity, especially in the tropics; (5) create living safeguarded databases of trusted information to reduce the risk of poisoning by AI hallucinated, or false, information; (6) ensure data generation is valued; (7) ensure respectful incorporation of Indigenous Knowledge; (8) ensure measurements enable the quantification of effectiveness of actions and (9) increase the resilience of global datasets to technical and societal change. Radical new collaborations are needed between computer scientists, engineers, molecular biologists, data scientists, field ecologists, citizen scientists, Indigenous peoples, policymakers, and local communities to create the rigorous, resilient, accessible biodiversity information systems required to underpin policies and practices that ensure the maintenance and restoration of ecological systems.

  PublisherOA PDFDOI

• The Earth BioGenome Project: Building the Ultimate Library of Life

  Frontiers for Young Minds · 2025-11-25

  articleOpen accessSenior author

  Earth is full of amazing life forms, from giant whales to tiny microbes. Scientists want to understand and protect this biodiversity—but first, they need to know what is out there. That is where the Earth BioGenome Project (EBP) comes in. This worldwide effort aims to read the complete set of genetic instructions (genomes) for every known eukaryotic species on Earth. These genome sequences can reveal how species are related, how they evolved, and how they might help us in the future. EBP scientists must collect high-quality samples, use special tools to read long pieces of DNA, and stitch those pieces together using powerful computers. Then they must figure out what the genes do and share the data with the world. It is a massive task—but if they succeed, the result will be a global library of life that could help protect species, improve health, and teach us more about how life works.

  PublisherOA PDFDOI

• The Biodiversity Cell Atlas: mapping the tree of life at cellular resolution

  Nature · 2025-09-24 · 6 citations

  review
  PublisherDOI

• The Earth BioGenome Project Phase II: illuminating the eukaryotic tree

  2025-09-18

  preprint1st authorCorresponding

  #### Sequencing the genomes of eukaryotic species through inclusive, global collaboration Discover the next phase of the [Earth BioGenome Project (EBP)](https://www.earthbiogenome.org/), which aims to sequence the DNA of all known eukaryotic species to protect biodiversity, improve global health, and drive scientific innovation. In their [Frontiers in Science lead article](https://www.frontiersin.org/journals/science/articles/10.3389/fsci.2025.1514835/full), the EBP leaders reveal a refined strategy to scale up the sequencing of 150,000 species. Thanks to major technical advances, high-quality genomes can now be produced 10 times faster and at significantly lower cost. Hear the authors discuss how EBP’s next phase will accelerate biodiversity research, support global conservation, and extend genomic benefits to underserved regions using mobile sequencing labs. Alongside a panel of fellow experts, they will explore the importance of open data sharing, training local scientists, and sequencing at the source—ensuring inclusivity, capacity-building, and benefit-sharing, especially in the Global South. If you would like to join, [register here](events.frontiersin.org/earth-biogenome-project/cassyni).

  PublisherDOI

• Introduction

  Annual Review of Animal Biosciences · 2025-02-18

  article1st authorCorresponding
  PublisherDOI

• Nine changes needed to deliver a radical transformation in biodiversity measurement

  2025-09-01

  articleOpen access

  Biodiversity is declining in many parts of the world. Biological diversity measurement and monitoring are fundamental to the assessment of the causes and consequences of environmental changes, identification of key areas for the protection of biodiversity or ecosystem services, determining the effectiveness of actions, and the creation of decision-support tools critical to maintaining a sustainable planet.

  PublisherDOI

• Genomic map of the functionally extinct northern white rhinoceros ( <i>Ceratotherium simum cottoni</i> )

  Proceedings of the National Academy of Sciences · 2025-05-13 · 2 citations

  articleOpen access

  The northern white rhinoceros (NWR; Ceratotherium simum cottoni ) is functionally extinct, with only two nonreproductive females alive. Efforts to rescue the NWR from its inevitable demise have inspired the exploration of unconventional conservation methods, including the development of induced pluripotent stem cells (iPSCs) for the in vitro generation of artificial gametes. The integrity of iPSC genomes is critical for in vitro gametogenesis to be used for assisted reproductive technologies using NWR iPSCs. We generated a chromosome-level NWR reference genome that meets or exceeds the metrics proposed by the Vertebrate Genome Project, using complementary sequencing and mapping methods. The genome represents 40 autosomes, an X and a partially resolved Y chromosome, and the mitochondrial genome. Using comparative FISH mapping, we confirmed a general gene order conservation between the NWR and horse genomes. We aligned the NWR genome with that of the southern white rhinoceros (SWR; Ceratotherium simum simum ), a population that has been physically separated from the NWR for tens of thousands of years, and we found that the two subspecies are very similar on the chromosome level. Comparing long-read data from NWR iPSC lines and the fibroblast cultures used for reprogramming, we identified copy number variations that were likely to have been introduced during in vitro iPSC expansion. The NWR reference genome allows for efficient, rapid, and accurate assessment of the genomic integrity of iPSC lines to direct their differentiation. This will assist in strategies to rescue the NWR through extraordinary measures like cloning and the generation of embryos from iPSC-derived gametes.

  PublisherOA PDFDOI

• Nine changes needed to deliver a radical transformation in biodiversity measurement

  2025-09-01

  articleOpen access

  Biodiversity is declining in many parts of the world. Biological diversity measurement and monitoring are fundamental to the assessment of the causes and consequences of environmental changes, identification of key areas for the protection of biodiversity or ecosystem services, determining the effectiveness of actions, and the creation of decision-support tools critical to maintaining a sustainable planet.

  PublisherDOI

Recent grants

• NIH Grant R01CA059148

  NIH · $366k · 1997

Frequent coauthors

• Kerstin Lindblad‐Toh

  Uppsala University

  164 shared

• Tomás Marquès‐Bonet

  Universitat Autònoma de Barcelona

  138 shared

• Elinor K. Karlsson

  115 shared

• W. Barendse

  112 shared

• S M Kappes

  110 shared

• Klaus‐Peter Koepfli

  Conservation Biology Institute

  110 shared

• J. E. Beever

  University of Tennessee at Knoxville

  108 shared

• Jeremy F. Taylor

  107 shared