YES

Problem:
 a__zeros() -> cons(0(),zeros())
 a__tail(cons(X,XS)) -> mark(XS)
 mark(zeros()) -> a__zeros()
 mark(tail(X)) -> a__tail(mark(X))
 mark(cons(X1,X2)) -> cons(mark(X1),X2)
 mark(0()) -> 0()
 a__zeros() -> zeros()
 a__tail(X) -> tail(X)

Proof:
 DP Processor:
  DPs:
   a__tail#(cons(X,XS)) -> mark#(XS)
   mark#(zeros()) -> a__zeros#()
   mark#(tail(X)) -> mark#(X)
   mark#(tail(X)) -> a__tail#(mark(X))
   mark#(cons(X1,X2)) -> mark#(X1)
  TRS:
   a__zeros() -> cons(0(),zeros())
   a__tail(cons(X,XS)) -> mark(XS)
   mark(zeros()) -> a__zeros()
   mark(tail(X)) -> a__tail(mark(X))
   mark(cons(X1,X2)) -> cons(mark(X1),X2)
   mark(0()) -> 0()
   a__zeros() -> zeros()
   a__tail(X) -> tail(X)
  Matrix Interpretation Processor: dim=1
   
   interpretation:
    [mark#](x0) = 4x0 + 1,
    
    [a__tail#](x0) = x0 + 4,
    
    [a__zeros#] = 0,
    
    [tail](x0) = 2x0 + 4,
    
    [mark](x0) = 4x0 + 7,
    
    [a__tail](x0) = 2x0 + 6,
    
    [cons](x0, x1) = x0 + 6x1 + 2,
    
    [zeros] = 0,
    
    [0] = 4,
    
    [a__zeros] = 6
   orientation:
    a__tail#(cons(X,XS)) = X + 6XS + 6 >= 4XS + 1 = mark#(XS)
    
    mark#(zeros()) = 1 >= 0 = a__zeros#()
    
    mark#(tail(X)) = 8X + 17 >= 4X + 1 = mark#(X)
    
    mark#(tail(X)) = 8X + 17 >= 4X + 11 = a__tail#(mark(X))
    
    mark#(cons(X1,X2)) = 4X1 + 24X2 + 9 >= 4X1 + 1 = mark#(X1)
    
    a__zeros() = 6 >= 6 = cons(0(),zeros())
    
    a__tail(cons(X,XS)) = 2X + 12XS + 10 >= 4XS + 7 = mark(XS)
    
    mark(zeros()) = 7 >= 6 = a__zeros()
    
    mark(tail(X)) = 8X + 23 >= 8X + 20 = a__tail(mark(X))
    
    mark(cons(X1,X2)) = 4X1 + 24X2 + 15 >= 4X1 + 6X2 + 9 = cons(mark(X1),X2)
    
    mark(0()) = 23 >= 4 = 0()
    
    a__zeros() = 6 >= 0 = zeros()
    
    a__tail(X) = 2X + 6 >= 2X + 4 = tail(X)
   problem:
    DPs:
     
    TRS:
     a__zeros() -> cons(0(),zeros())
     a__tail(cons(X,XS)) -> mark(XS)
     mark(zeros()) -> a__zeros()
     mark(tail(X)) -> a__tail(mark(X))
     mark(cons(X1,X2)) -> cons(mark(X1),X2)
     mark(0()) -> 0()
     a__zeros() -> zeros()
     a__tail(X) -> tail(X)
   Qed