Dear Dr. Agrawal,
My name is Dana Church and I live in Waterloo, Ontario, Canada. I studied bumble bees for my PhD at the University of Ottawa. I am also a children’s author. My upcoming nonfiction book for middle-grade readers (aged 8-12), entitled, “The Beekeepers: How Humans Changed the World of Bumble Bees” will be published by Scholastic on March 1, 2021.
The reason I am writing to you is I am working on my next book, which focuses on monarch butterflies. I read your book, Monarchs and milkweed: A migrating butterfly, a poisonous plant, and their remarkable story of evolution. It is absolutely wonderful! I so appreciate your writing style, which is a lovely balance of scientific and lay language. I strive for that myself in my writing. All of your anecdotes are so interesting. There is a nice amount of humour, too. It is like you are sitting having coffee with your reader, telling them all about monarchs and milkweed, rather than feeling like you are reading a book! It is also a treasure trove of information for me as I write my own book. There is so much important information that I don’t think I would have otherwise found myself. Thank you so very much for writing Monarchs and milkweed!
After reading your book, I have some (quick?) questions about cardenolides that I am hoping you can answer. Maybe I missed something in my reading, but where are cardenolides stored in milkweed leaves exactly? In the actual cells of the leaf? Are the poisons in latex different, or are cardenolides stored in latex too?
Thank you so much for your time! Best wishes, Dana, danachurchwriter.wordpress.com
Thanks so much for your kind words, they made my day! Here are quick answers to your questions: Cardenolides are in all milkweed tissues roots, leaves, latex, seeds, and even nectar). Where they are exactly stored in terms of the cellular structure is not known, but they are not only in the latex (neither roots, seeds, nor nectar have latex). In some milkweed species, cardenolides are concentrated 100-1000 times in the latex, but in common milkweed, cardenolides in latex are fairly low in concentration. Latex has several other toxins, in addition to cardenolides, including the sticky material (rubbers) and cysteine proteases, among others.
All my best! -Anurag