Rejection of valid theories of biology on theoretical grounds
The idea that organisms with mitochondria derive energy from respiration through a proton motive force was considered controversial at the time.

This is the best reference I could find at the time:


  His theory explained that it was the energy captured from those protons
  returning to the matrix and not energy stored in an undefined
  high-energy covalent chemical intermediate that was then used to drive
  ATP synthesis. This Nobel Prize-worthy concept (1978) was so counter
  to the leading theories of the day that the field spurned it for the
  better part of a decade.


Pagliarini, D.J., Rutter J. Hallmarks of a new era in mitochondrial biochemistry 2013  Genes Dev.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3877752/