my hegelian synthesis (this argument is really a false dichotomy. gould was a gradualist, too. his supporters misrepresented him.) argues that the error is really in the cladistics model rather than a debate over evolutionary theory. due to linnaeus, and ultimately due to aristotle, who attributed a crude evolutionary theory to the "chaldeans", we've been using the wrong mathematical model to imagine evolution for centuries and centuries. we use something called directed graphs to model evolution - trees. we refer to the tree of life. this is inherently hierarchical and intuitively erects theocratic conclusions that aren't actually supported by the data. in the dna era, the solution to the underlying gould-dawkins debate has increasingly been identified as hybridization, which the models previously rejected as theocratically deviant, but which more and more data has increasingly identified as repeatedly arising naturally in areas where ecological niches overlap. contemporary environmentalists may be surprised to learn that polar bears are on a path towards genetic introgression back into the grizzly population and that it's being increasingly realized that this is a general demonstration of actual natural selection in real life, due to climate change, which happens often. this evolution is normal. the ideal of nature in a fixed state is not science, it's conservative religious ideology.
another example is the interbreeding of coyotes and wolves in eastern canada, which would create a large shift in the fossil record. coyotes all of a sudden are going to increase in size. it's the wolf dna and we know it.
so, the premise of all of these different species in the human fossil record is dubious. every researcher wanted their own species. every minimal change was presented as a novel variation. the question of whether they could fuck or not requires more rigour, and we can assume that they did if they could, and probably tried even if they couldn't.
a better mathematical model for evolution is a complicated graph with crossings that captures hybridization events (often due to climate change), which actually appear to be an extremely common evolutionary mechanism.
the footprints themselves may not hold up to scrutiny but it's not the more important point. the more important point is that the hierarchical spencerian tree model is ignorant and backwards and it's theological implications are consequently wrong. evolution is stochastic, statistical, chaotic. natural selection cannot be assumed, it must be proven that the shifts in population genetics are not genetic drift, which is a null hypothesis. the graph theory is more complex, but it's also a rich and profound theory.