Maintenance work on the ZORA databases is scheduled for Wednesday 22 May 2019 from 20:00-22:00. During this period ZORA and JDB will not be available. Thank you for your understanding.
Stalleicken, J; Mukhida, M; Labhart, T; Wehner, R; Frost, B; Mouritsen, H (2005). Do monarch butterflies use polarized skylight for migratory orientation? Journal of Experimental Biology, 208(12):2399-2408.