Back Door Snow Drift

A good day to sit at the computer and see if I could find answers to some questions that had been bothering me for awhile.   Tackled the easiest one first - Do black bears have to hibernate?  There was a news story about a 500 lb bear in Colorado that was raiding garbage cans in February.  That begs the question "Why isn't the bear hibernating that time of year?'  First, the Internet let me know that no large mammal actually hibernates.  What bear do is enter a state of torpor where every few days they warm up their body.  However, the Internet pointed out that zoo bears which are constantly fed throughout the winter don't hibernate and neither do non-pregnant bear in warmer climes.  So given access to food and shelter from the elements, bear don't necessarily need to 'hibernate' during the winter months.  Next question is "Do wombats pee?"  Coincidentally,  around the same time I read a book and watched a documentary  both mentioning that wombats poop square cubes of scat.  It is caused by the wombat's intestinal system which tries to squeeze every last bit of water from food passing through the body.  So my question was 'Given the extremes that the wombat has evolved to retain water, why would they pee?"  Turns out they do pee - not often and not concentrated - but they do.  Couldn't find out much else - most documentation on wombat excretions were focused on the cube shaped poop.  Might be it's an overflow mechanism mammals have to handle water plus it acts as a scent marker to say "I'm in the mood for love."  The last question is "Do some aphids die from eating milkweed?"  I'd recently read a book on butterflies.  It claimed a third of monarch caterpillars die because they can't handle the toxic milkweed sap or their mouth pieces get gummed up in the thick sap.  I'd never heard of that before but it made me wonder if aphids I see tended by ants on milkweed experience the same issues.   That one will take more research.  All the articles I read were more concerned about how to get rid of aphids rather than their life cycles.    Will have to remember to write down more 'burning' questions to research during the next snowstorm.