S10-1

Bridging a gap between genomics and culture for understanding human evolution

Hiromi Matsumae¹

¹Tokai University

Human culture, including language and music, is one of the distinctive characteristics of our species. Culture plays an essential role in the evolutionary history of humans and can be positioned as memes or similar to phenotypes and environmental factors. In early studies, anthropological geneticist L.L. Cavalli-Sforza proposed relationships between genes and culture in the 1980s. Quantitative studies of cultural evolution are still developing even in the 2020s, while the burst of anthropological genomics has provided us a high-resolution of human evolutionary history. For example, drawing phylogenetic trees using vocabulary are the standard way to discuss genes and language relationships. However, the lexical trees can be applied for only languages with low diversity (in other words, the methods target languages within the same language family, such as the Indo-European languages in West Eurasia and the Austronesian languages in the Asia Pacific). Therefore, the genes-language relationships in high linguistic diversity areas, such as 11 language families in Northeast Eurasia, were not well-understood. To address the gap between genomics and cultural evolution, we established an integrated statistical analysis to explore genetic and cultural (language and music) variation in Northeast Eurasia. We found the first evidence that the structure of language (grammar) correlated with genetic history beyond language families, but not with vocabulary, sounds of language(phonology), and music(songs). This result suggests that culture may evolve with genomes but sometimes may not. Digitalizing human culture could be a new tool for the systematic understanding of human evolution cooperating with genomic data.

S10-2

Evolution and mechanisms of carnivorism in nematode-trapping fungi

Yen-Ping Hsueh¹

¹Academia Sinica

Nematode-trapping fungi (NTF) are a group of specialized microbial predators that consume nematodes when food sources are limited. Predation is initiated when conserved nematode ascaroside pheromones are sensed, followed by the development of complex trapping devices. To gain insights into the coevolution of this interkingdom predator–prey relationship, we investigated natural populations of nematodes and NTF that we found to be ubiquitous in soils. Arthrobotrys species were sympatric with various nematode species and behaved as generalist predators. The ability to sense prey among wild isolates of Arthrobotrys oligospora varied greatly, as determined by the number of traps after exposure to Caenorhabditis elegans. While some strains were highly sensitive to C. elegans and the nematode pheromone ascarosides, others responded only weakly. Furthermore, strains that were highly sensitive to the nematode prey also developed traps faster. The polymorphic nature of trap formation correlated with competency in prey killing, as well as with the phylogeny of A. oligospora natural strains, calculated after assembly and annotation of the genomes of 20 isolates. A chromosome-level genome assembly and annotation were established for one of the most sensitive wild isolates, and deletion of the only G-protein β-subunit–encoding gene of A. oligospora nearly abolished trap formation. In summary, our study establishes a highly responsive A. oligospora wild isolate as a model strain for the study of fungus–nematode interactions and demonstrates that trap formation is a fitness character in generalist predators of the nematode-trapping fungus family.

S10-3

Reconstruction of evolutionary process and pathways: Lessons from camouflage and mimicry patterns in butterfly wings

Suzuki, TK¹

¹Graduate School of Science, the University of Tokyo

One of the greatest mysteries in evolutionary biology is how complex and exquisite animal structures evolved, such as flounders with one-sided eyes, butterflies that look just like dead leaves, and elaborate animal eyes. Traditionally, this has been revealed through the use of fossil records. However, for many traits, fossils have not survived and are even difficult to obtain. So, how can we overcome this difficulty? Recently, I have developed a comprehensive mathematical analytical method for solving macroevolutionary processes (ref. 1). This method is based on multicomponent structures of traits and is combined with phylogenetic comparative methods. In this talk, I will show this new mathematical method with a brief overview of historical backgrounds. As an example of the use of this method, the evolution of a butterfly that mimics dead leaves will be introduced (ref. 2). Furthermore, by extending this method, I developed a method for analyzing macroevolutionary pathways. This provides evolutionary dynamics of morphological traits, in which morphological diversification and complexity evolved together with changing the combination of its components. References: 1. Suzuki (2017) On the Origin of Complex Adaptive Traits: Progress Since the Darwin Versus Mivart Debate. J Exp Zool B 328:304-320. 2. Suzuki, Tomita, Sezutsu (2014) Gradual and contingent evolutionary emergence of leaf mimicry in butterfly wing patterns. BMC Evol Biol 14:229.

S10-4

Ant genera that colonized Madagascar diversified along different evolutionary axes

Nicholas R. Friedman¹, Francisco Hita Garcia¹, Georg Fischer¹, Bonnie Blaimer², Doug Booher³, Julian Katzke¹, Lazzat Aibekova¹, Alexander Mikheyev^1,4, Brian Fisher⁵, Evan P. Economo¹

¹Okinawa Institute of Science and Technology Graduate University
²Museum für Naturkunde - Leibniz Institute for Research on Evolution and Biodiversity
³Yale University - Department of Global Change and Biodiversity
⁴Australian National University - Division of Ecology and Evolution
⁵California Academy of Sciences

The degree to which evolution follows stable deterministic trajectories, or is contingent upon history and local conditions, has been the subject of debate for many decades. To address this issue on the scale of millions of years, comparison of repeated events of colonization and adaptive radiation may provide a relatively controlled “evolutionary experiment”. Here, we describe the diversification trajectory of six independent colonizations of Madagascar by five genera of ants encompassing 500 species. We estimated phylogenies for each genus, measured morphology using micro-CT and geometric morphometrics as well as traditional techniques, and estimated climatic preferences based on species ranges. If evolution tends to be deterministic, we should expect to see each genus diverge along similar evolutionary axes in a similar order (for example, body size then climate). Instead, we observed that each genus tended to diverge along a different evolutionary axis. Some patterns did emerge that warrant further exploration, in particular the tendency of body size to diverge early in the history of each colonization, and the tendency of thorax shape to diverge late. Together, these results suggest that while some features of an adaptive radiation can be predictable in a rough sense, its direction is likely to be dependent on initial conditions during colonization rather than an intrinsic evolutionary program.

S10-5

Making sense of macroevolutionary genotype-phenotype associations in the light of convergent evolution

Kenji Fukushima¹

¹University of Wuerzburg

The conjecture that common genotypes are responsible for common phenotypes has revolutionized modern biology. In the last two decades, hundreds of thousands of genotype-phenotype associations have been discovered in diverse organisms, including humans, mainly by the genome-wide association study (GWAS). However, successful analyses have mostly been limited to within-species comparisons, and major challenges lie in analyzing multiple species with ancient evolutionary divergence. This situation has greatly hindered the study of macroevolutionary traits, although it should be possible to statistically evaluate genotype-phenotype associations for any trait, especially if it has evolved many times convergently. The prevalence of phenotypic convergence is underpinned by various examples throughout the entire tree of life, from echolocation in animals to carnivory in plants. To unlock the potential value of convergent evolution in studying macroevolutionary traits, we developed new methods to detect molecular convergence in protein sequences and gene expression and to correlate those evolutionary events with phenotypes. In this talk, I will present our recent effort to shed light on genotype-phenotype correlations in macroevolutionary traits, even for groups of organisms that diverged for hundreds of millions of years.