What is true of macro-evolution?

Answer 1

It is true that speciation occurs. Since macro-evolution is defined as evolution at and above the species level, this makes the statement that macro-evolution occurs an independently verifiable fact.

It is also true that in Biology we find nested hierarchies at every level - both at the range of observation from the molecular to the morphological, and at the range of groups from the single species to life-kind in general. This is precisely what we would expect if common descent were true not just within the genus, but for all known life.

Furthermore, it is true that we find morphological intermediates in the fossil record: forms that are intermediate morphologically between basal clades in the nested hierarchies of life and clades derived from those basal clades. A basal clade is a group of organisms linked by shared features; a derived clade is a group within that larger group that shares all those features, but is also linked by a distinct set of features present only within that smaller group. An example of this is the basal clade of Apes, and the derived clade of Great Apes, between which exists, for instance the transitional form Pierolapithecus catalaunicus. This, again, is exactly what we would expect to find if macro-evolution were not just true for minor taxa (eg. within a genus), but for all taxa, throughout time.

There are many statements about macro-evolution that have been verified through observation. The complete list of possible truths about macro-evolution is too large to detail in a single answer.

Answer 2

Macroevolution is merely the continuation of microevolution over time, and not always all that much time. There is no real difference between macro and microevolution; evolution and speciation.

Evolution is the change in allele frequency over time in a population of organisms.

In the right environment and geographic isolation the alleles changing over time can change the organism into a new species along a branching continuum of change.