I tracked down Kojonen’s book, which has this to say:
As biologists increasingly talk of “laws of form” underlying evolutionary development, the role of natural selection and mutation in explaining biological form seems comparatively less all-encompassing. The resulting picture comes quite far from the old view that all one needs for evolution is differential survival, reproduction, and heritability, evolution then following from these as almost a logical necessity. Again, the basic trend of research has been visible for some time. Sean Carroll (2001, 62) wrote that:
Life’s contingent history could be viewed as an argument against any direction or pattern in the course of evolution or the shape of life. But it is obvious that larger and more complex life-forms have evolved from simple unicellular ancestors and that various innovations were necessary for the evolution of new means of living. This raises the possibility that there are trends within evolutionary history that might reflect the existence of general principles governing the evolution of increasingly larger and more complex forms.13
Unfortunately Kojonen takes this Carroll quote from a secondary source. The original source continues on:
The first task of this review is to examine the degree to which the evolution of the shapes of life are a matter of chance — a random walk in morphospace — or of necessity — borne from the demands of natural selection and the constraints imposed by physics, genetics and development. The second task is to extrapolate from the evolutionary trends on Earth to assess what they might portend for the evolution of life elsewhere.
This ‘review’ concludes:
The parochial question nested within the mystery of the existence of life on other bodies is that of the existence of forms like the ones that have occurred on Earth. A few extrapolations seem to be reasonably grounded in the overall trends of life’s history reviewed here. Assuming a cellular basis of life elsewhere, the passive trends towards increases in organismal size, complexity and diversity from some initial minima are certain to prevail in any system. It must be kept in mind, however, that few macroscopic forms evolved in the first 3 billion years of life on Earth. Therefore, the time required for any quantum change in morphology is entirely contingent upon the particular history of any system. As for the shapes of life, macroscopic forms are most likely to be multicellular and there is a finite set of simple geometries — such as those that dominated the early history of life on Earth (linear and branched filaments, cylinders and spheres) — that are likely to satisfy the constraints imposed by diffusion and biomechanics and that are therefore likely to be universal 2,75 .
But the evolution of motile, modular mega-organisms may be a different story. Only after 3 billion years of physiological and anatomical evolution, vast changes in the environment and ecology (that were partly biogenic in nature), and extensive genetic and developmental innovations did such beasts emerge on Earth. And, although some symmetrical body organization is likely of macro- forms 75 , there is no basis to assert that bilateral, radial or spiral forms were or would be inevitable. Nor, sadly, is their continued evolution assured as the ecological dice are now in the hands of a single species that is on a path to extinguishing a substantial fraction of all diversity before the question of life elsewhere may be answered.[1]
This does, I think, alter the in-context meaning of the original quote considerably.