Bloodflowers’ risk to monarchs could multiply as climate changes
Heat and CO2 scenarios suggest a milkweed species becomes toxic or useless to caterpillars
![monarch butterfly on tropical milkweed](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2018/07/071018_sm_monarch_feat_REV.jpg?fit=860%2C460&ssl=1)
MONARCH BEWARE As the climate changes, lovely tropical milkweed popular in gardens may become even more of a danger to monarch butterflies than it is now.
Warren Price Photography/Shutterstock