Biological and psychosocial impact of isolation in aninmals

I somewhat suspect this is a biased list of animal research and
isolation but it's pretty darn interesting. I'm not sure how the same
sort of biological science could be applied to lonilness in humans -
measurement requires human contact.

From
http://www.ncbi.nlm.nih.gov/pubmed/19968414
Alone in the Crowd: The Structure and Spread of Loneliness in a Large
Social Network
Nicholas A. Christakis

"
Social isolation decreases the lifespan of the fruit fly, Drosophilia
melanogaster (Ruan & Wu, 2008); promotes the development of obesity and
Type 2 diabetes in mice (Nonogaki, Nozue, & Oka, 2007); delays the
positive effects of running on adult neurogenesis in rats (Stranahan,
Khalil, & Gould, 2006); increases the activation of the
sympatho-adrenomedullary response to an acute immobili- zation or cold
stressor in rats (Dronjak, Gavrilovic, Filipovic, & Radojcic, 2004);
decreases the expression of genes regulating glucocorticoid response in
the frontal cortex of piglets (Poletto, Steibel, Siegford, & Zanella,
2006); decreases open field activity, increases basal cortisol
concentrations, and decreases lymphocyte proliferation to mitogens in
pigs (Kanitz, Tuchscherer, Puppe, Tuchscherer, & Stabenow, 2004);
increases the 24-hr urinary catecholamines levels and evidence of
oxidative stress in the aortic arch of the Watanabe heritable
hyperlipidemic rabbit (Nation et al., 2008); increases the morning rises
in cortisol in squirrel monkeys (Lyons, Ha, & Levine, 1995); and
profoundly disrupts psychosex- ual development in rhesus monkeys (Harlow
et al., 1965).
"