From: 69jpil69@gmail.com   
      
   On Mon, 07 Jul 2025 08:00:09 -0700, Bob Casanova    
   wrote:   
      
   >On Mon, 7 Jul 2025 07:01:51 -0500, the following appeared in   
   >talk.origins, posted by RonO :   
   >   
   >>On 7/6/2025 10:09 PM, Pro Plyd wrote:   
   >>>    
   >>> https://indiandefencereview.com/its-official-dolphins-and-orcas-have-    
   >>> now-crossed-the-point-of-no-return-in-their-evolution-of-returning-to-    
   >>> land-again/   
   >>>    
   >>> Dolphins and orcas, revered for their intelligence   
   >>> and agility, have reached a pivotal point in their   
   >>> evolutionary journey. New research has revealed   
   >>> that these marine mammals, once land-dwellers, have   
   >>> evolved to a stage where returning to life on land   
   >>> is biologically impossible. A breakthrough study   
   >>> underscores that after millions of years of   
   >>> evolutionary change, dolphins and orcas are now   
   >>> forever bound to the ocean.   
   >>>    
   >>> Published in Proceedings of the Royal Society B,   
   >>> the study scrutinized over 5,600 mammal species   
   >>> to understand how dolphins and orcas evolved from   
   >>> semi-aquatic ancestors to fully marine life forms.   
   >>> The research, led by Bruna Farina, a PhD candidate   
   >>> at the University of Fribourg in Switzerland,   
   >>> concludes that the transition from semi-aquatic to   
   >>> fully aquatic is a one-way path. Once a species   
   >>> makes this leap, its evolutionary direction becomes   
   >>> irreversible.   
   >>>    
   >>> Farina’s team found that this transition occurred   
   >>> millions of years ago when mammals returned to the   
   >>> sea. Unlike their terrestrial predecessors, dolphins   
   >>> and orcas cannot evolve back to a land-based   
   >>> lifestyle. Their adaptations—such as specialized   
   >>> limbs, unique diets, and reproductive systems—have   
   >>> become so ingrained that reversing these traits is   
   >>> no longer possible.   
   >>> ...   
   >>>    
   >>> The paper is here   
   >>>    
   >>> https://royalsocietypublishing.org/doi/10.1098/rspb.2023.1099   
   >>> Dollo meets Bergmann: morphological evolution in   
   >>> secondary aquatic mammals   
   >>>    
   >>Never say never.  How did fish adapt to terrestrial life styles?    
   >>Dolphins already have lungs.   
   >>   
   >The whole thing sounds to me like "We can't imagine how this   
   >could be accomplished, so it can't; simply too many   
   >simultaneous changes are required", an assertion more   
   >familiar from evolution denialists than from (supposed)   
   >scientists. I wonder if they think that cetaceans became   
   >semiaquatic (not fully; they still can't breathe underwater)   
   >in one fell swoop? And if not, why the same gradual process   
   >won't work in reverse?   
      
      
   It's a matter of probability.  Between random genetic events and   
   random environmental events, it's almost impossible for any *exact*   
   evolutionary pathway to be repeated.  It would be like a broken glass   
   reassembling itself.   
      
   --    
   To know less than we don't know is the nature of most knowledge   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)