Cowling, S.A. and Sykes, M.T. 1999. Physiological significance of low atmospheric CO 2 for plant-climate interactions. Parmesan, C., Ryrholm, N., Stefanescu, C., Hill, J.K., Thomas, C.D., Descimon, H., Huntley, B., Kaila, L., Kullberg, J., Tammaru, T., Tennent, W.J., Thomas, J.A. and Warren, M. 1999. Poleward shifts in geographical ranges of butterfly species associated with regional warming. Thomas, C.D. and Lennon, J.N. 1999.
Birds extend their ranges northwards.