I had heard about torpor, but didn’t know it was so deep. No reply is necessary.

Their tongues wrap around their heads like woodpeckers. Torpor with infared cameras is amazing.

I had no idea that their body temperature can vary so drastically. How does that compare with other birds?

I was really surprised by nectar robbing. I don't get why some hummingbirds do it and others don't.

The fact that they can migrate such large distances as other larger birds, it's indeed one of the most magical fact to understand about these precious creatures. Also the color reflecting phenomenon on their feathers is pretty amazing, never thought it would be such complex mechanism that lets these birds to look like magical buddies.

I was surprised that it would take 20 to 30 minutes for a hummingbird to 'awaken' from torpor, how vulnerable they are.

I was surprised that torpor drops the body temperatures so much. I knew they there torpor to use less energy, but this is more extreme than I was expecting. Also, I have seen hummingbirds use their tongues, but didn't realize how it worked nor how long they are! So cool!

I loved learning how they angle their wings so that they get thrust on both the upward and downward wing beat.

The location of their tongue when not in use surprised me.

I had concerns that hummingbirds wouldn't be able to reach the nectar in a feeder if the water level dropped. I hadn't thought about tongues and the novel structure and use. So interesting. I am learning so much.

I didn't realize that there are so many species or that they only reside in the Western hemisphere. I learned that the males do not participate in nest-building or raising of the chicks.

everything about hummingbirds surprises and delights me! I thought I knew something about them, but this class has taught me so much more.

Great lesson! What little warriors being able to do all the wing maneuvers and how their tongue works. Also, just how hot they are and how cool they can get while being in torpor! I have heard that sometimes they can/will hang upside down in torpor. Would anyone know why this is?

I did not realize some birds utilize tree sap to supplement nectar, especially early in the season.

The way their tongues work really surprised me. I’d envisioned a simple straw, which would probably require way too much effort to use.

I have learned so much with this course! Everything is fascinating about these tiny creatures!

I was amazed at how the hummingbird’s tongue works and rests when not in use. I loved to hear about how they get into a torpor to save energy.

Torpor fascinates me. I have only seen hummingbirds cone to my feeder or the Trumpeter Vine.  The hummingbirds would be vulnerable to predatory birds when in a torpor state. Can their feet clutch a branch to perch.

That they could die so quickly without nourishment

It never occurred to me that the bone composition and structure were similar to humans. It certainly makes sense but I never thought about it. Another fascinating item was the mechanics of how the hummingbird wing works in order to hover.

Absolutely, I was amazed at how their tongues are structured and how they work, I've seen them put out their tongues many times before, but never even imagined how they sip with them.

Also the way in which they move their wings, what an incredible adaptation.

The iridescence topic was also eye opening.

Yes! I continue learning many things about these fabulous birds. For example, I didn't knew that hummingbird's diet was 90% of nectar and only 10% of insects and anthropods. Also, the last lesson talking about how these birds cool down their body temperature at night to save energy is amazing.

I was amazed to learn about how their tongues work! Such incredible design! It makes more sense now on how they are able to drink nectar. I think it is also cool how their tongue curls around their skull in a way similar to wood peckers.

All very fascinating. Amazing birds.

I didn't realize the variety of bills and sizes of hummingbirds, the diversity is amazing! I also didn't realize that hummingbirds spent so much time not flying (75%!) and learning about Torpor was facinating! I also loved learning about the difference in a hummingbirds anatomy compared to an average bird; their wings are amazing!