Warming up!!!
 

I was just told by my band that I shouldn't have to warm up before we jam. They said I should be ready at all times. How do you feel about that?

I think your band is full of it.

Since you're asking: it's total nonsense.

I know that this is a little different, but I remember seeing David Draiman on 'That Metal Show' and he was talking about when he met Dio. David said that when he asked Dio what he did to warm up before a show. Dio said, if you have to warm up, you don't have it.

Around 1:15
http://www.youtube.com/watch?v=5noszXlfbE0

That always stuck with me a little, but I still like to warm up if I can. It just feels better. (I guess I don't have it either :p)

Who cares what your bandmates think? If you want to warm up, warm up. It's better to be confident in your playing rather than worry about whether or not you would be playing better if you HAD warmed up.

Well, you shouldn't waste band time doing your own warmups---warm up while the drummer is setting up or something. :)

Sounds like you are in earnest and they are being smart asses! In all honesty though, just stretch your wrist and get at it!

Warming up is a vital part to any player, you can ignore the vanity advice of those that say "just do it" or " if you have to you don"t have it" etc is all talk, and cheap talk at that?

Proof of it...I have yet to find anyone that has used warm ups and stretches over nothing that confirm or agree that doing nothing is better.
Actually I worked with a player who was so set in his ways warming up was rubbish, to make my point i suggested moving a quite intense song to the opening number he said "it will not work there....it's to early in the set." When I pushed him to explain he said "it's one of those songs where you need a few under your belt to get the best from it." So I pushed him again, "well its easier to play it when you have got in to the set."
I pushed him a few more times but he would not use the phrase "warm up", he would use everything that eludes to a warm up, everything that is essential does what a warm up does, be he would not use the word warm up.

Point of fact, if you play regular, as in every day warming up is how you start out. Most players ease into a practice, so even though they do not warm up, they actually do what a warm up does.
But if you have to go straight on and perform, then using warm ups and stretches of any sort will greatly benefit you in the long run. :)

Well that's (at least for me) a bunch of crap! I play fast, and I play hard on my strings, so I need strength and speed from my muscles. A couple of our fastest songs are in the beginning of the usual setlist.
Years back I thought so, too. Just go on stage, play a bit, it will all be fine. But looking back at videos from that time now, it was everything but tight and I can see why. Muscles are not warmed up, I can see how I have to fight cramping of fingers until the muscles are really warmed up (but of cause wrongly warmed up). I am left-handed but play right-handed, so I have to fight a contineous handycap concerning natural strength-balance between my left and my right hand, anyway.
Since a couple of years, I always warm up (gigs, rehearsal, jams...) - but I know now that making music at the "not-semi-professional-but-no-amateur-either" level requires fitness. I stopped smoking 2 years ago and I go to the gym 4 times a week (not only for making music, of cause - I also want to be fit in general :) ). Warming up is a very very important thing to do - if your hobby is cycling or jogging, you also warm up, right? Playing any instrument seriously requires a bunch of movement, so your muscles need to warm up. Ask any first-year sports-student at your local university, it's the first thing they learn!
In my band, we all warm up a couple of minutes. Everybody has his own kind of movement-combinations for a couple of minutes, then we jam 5 minutes to get the feeling - and then we go!

From Talkbass I learned some special warming-up methods and daily trainings for more strength and speed in your under-arms and fingers, which also makes a world of a difference (I asked a couple of personal trainers at my gym, but none can show you training methods for your fingers ;-) )

PS: Watch some concert-DVDs with extras (every Iron Maiden DVD will do). Watch youtube movies "behind the stage". Every band that tries to work seriously does warming-up sessions. Heck, Metallica has an own rehearsal room backstage :-)