Title of thread is not necessarily accurate, I'm afraid.
First of all, we can only assume, not actually know, an animal's emotional state at any given time.
Secondly, you're contradicting yourself by first saying they howl for sadness and loneliness, and then saying also to howl with their families.
Why wouldn't a rally with friends and family, which often includes a chorus howl, indicate excitement and/or joy? If we are going to assume animals' emotional states during behavioral displays, why ignore the probable emotions going on during THESE howls?
Replying "well that is a howl to protect the territory" or give some other reasoning based on the survival functionality of it is not a refutation.
Because here's the thing: yes, howling can be communicative in a lot of ways. But the driving factor for much of animal behavior is not cognitive, higher-level reasoning. Wolves are *probably* not thinking "we should all wag our tails and nuzzle each other wildly and howl right now, because that is a good idea that will help us bond and warn others from our home turf." They're probably feeling SOMETHING that is driving them to behave the way they are.
Put better, in this article
Quote:Instead, the primary basis of vertebrate vocal communication is believed to be emotion (Suddendorf 2013), a conclusion reached by Charles Darwin in The Expression of Emotion in Man and Animals (which is still widely quoted). Even in chimps, “the production of sound in the absence of the appropriate emotional state seems to be almost an impossible task” (Goodall 1986). We share many midbrain structures for emotions with other vertebrate species. Included in the term “emotion” are the concepts of “internal drives” (Grandin 2005) or “internal motivational states” (Lord et al. 2009). Were 302’s howls that day really motivated wholly or in part by hunger, exploratory behaviour, or care soliciting? Possibly those innate feelings caused adaptive neurohormonal adjustments in him; excitation of the sympathetic nervous system resulted in more cortisol or other biochemicals in the blood, and the result was that he howled. The biochemistry of emotions is a complex and active research area. If the outcome of such howls often enough was that the pack joined in on what turned out to be successful hunts, then natural selection would favour howling in that particular context without having any reasoned-out intent.
My point here is that even calls that have survival function (as opposed to "just" communication or something? I'm not even sure we can really separate such things out), ALSO cannot be assumed to be independent of emotion.
These topics are very complex.
I think it would also probably be beneficial to be more specific about what we mean about "excitement." Do we mean excited, energetic joy? Or do we mean being in an excited / more highly stimulated mental state? As someone who has worked with wolves, I would say either seems likely to be a facet of howling behaviors, as with the "joyous" looking rallies OR when there is an appropriate excitatory stimulus (eg: many of our animals would get worked up by sirens or train whistles and begin howling).