Major new models for the evolution of new species have been developed since Darwin’s time. One is termed punctuated equilibria with bursts of new speciation (punctuations) followed long periods of no change (equilibria). Another is allopatric speciation or speciation by geographic isolation. A third is the finding that when new species develop it may rapidly accelerate the development even more new species. All play a role in speciation and would leave behind few if any transitional or intermediate forms. Thus, rather than falsifying the theory of evolution, when speciation takes place by these mechanisms, the absence of transitional forms is the expected outcome.[p68]
Fossil
Intermediates in Evolution 
And the list [of intermediates] goes on and on. Intermediate fossil organisms transitional between reptiles and birds, reptiles and mammals and other taxonomic groups have also been described. Many of these intermediates have been found only recently. The finding of these intermediate fossils validate Darwin's assumption that in many cases "missing" intermediates would be found with time. They increasingly have been.
While intermediate or transitional forms are commonly missing, when the fossil record is very complete, the intermediate forms are often observed. When all of the above observations on the different mechanisms of speciation are considered it is clear that the apparent lack of some intermediate forms does not disprove the theory of evolution. [p76]
