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Using techniques from singular perturbation theory, we explicitly calculatethe cosmological evolution in a class of modified gravity models. Byconsidering the (m)CDTT model, which aims to explain the current accelerationof the universe with a modification of gravity, we show that Einstein evolutioncan be recovered for most of cosmic history in at least one f(R) model. We showthat a standard epoch of matter domination can be obtained in the mCDTT model,providing a sufficiently long epoch to satisfy observations. We note that theadditional inverse term will not significantly alter standard evolution untiltoday and that the solution lies well within present constraints from Big BangNucleosynthesis. For the CDTT model, we analyse the ``recent radiation epoch''behaviour (a \propto t^{1/2}) found by previous authors. We finally generaliseour findings to the class of inverse power-law models. Even in this class ofmodels, we expect a standard cosmological evolution, with a sufficient matterdomination era, although the sign of the additional term is crucial.

Standard Cosmological Evolution in a Wide Range of f(R) Models