If, as you say, some individuals who call themselves Neo Darwinists "seem
rather chary of macroevoltuionary notions", they aren't really Neo Darwinists
in my opinion. Ideas about evolution had been around before Darwin. His
contribution was that evolution happened by natural selection working upon
small, gradual, purposeless, random mutations. Although Darwin himself didn't
actually insist mutations had to be random; he accepted the possibility of
some form of Lamarckism. Neo Darwinism defines mutations as "random" and
without purpose. That is the definition of Neo Darwinism. It is not that
think macro evolution could not have happen this way. I think the fossil
record indicates macro didn't happen gradually. In my opinion the mechanisms
of macro evolution are completely unknown.
In the absence of plausible mechanisms of macro evolution, all explanations
can be considered at this point, including:
Design. It seems arrogant for any scientist to state he knows life is not
the result of any design.
Special creation. Unless you believe in gradualism, the creation of
radically different organisms can certainly be viewed as special.
Senapathy's belief that the pattern for the mature organism was contained in
the original DNA, while eminently naturalistic, could be viewed as "special
Forms of Lamarckism, such as mutations influenced by "use" (Spetner). ("Use"
can be directed to some degree by "will", something science will probably
remain unable to measure.)
Symbiosis--which could also include an element of "will". (Margulis doesn't
speak kindly of Neo Darwinism, and I suspect most militant neo Darwinists
remain hostile to holism and the Gaia concept.)
DNA which is alive and creative (unexplainable by science, and not definable
by mathematics at this point). Who could state with certainty that creative
DNA could not be the result of a design? ( Kauffman, of "intricate order",
also does not speak kindly of neo Darwinism.)
Panspermia. Lots of interesting ideas here, and the panspermia people are
outspoken in their criticism of Neo Darwinism.
I see no reason to try to "outlaw" consideration of any combination of these
and other possibilities, as the defenders of Neo Darwinism seem eager to do.
Hopefully, most of the combative "defenders of neo Darwinism" aren't real
scientists. Many of the best scientists must surely be busy searching for
alternatives to gradualism.