“If evolution really works, how come mothers only have two hands?” is a jocular saying about mothers that has been printed on many images. “DELAY: If evolution really works, Ed Dussault asks, how come mothers still have only two hands?” was printed in the Centre Daily News (State College, PA) on December 21, 1976. Ed Dussault probably wrote the line that month for the Saturday Evening Post.
 
“If evolution works, how come mothers still have only two hands?” was the early form of the saying, but around 2000, it came to be written as, “If evolution really works, how come mothers only have two hands?” Also around 2000, American comedian and actor Milton Berle was credited as the author, but there is no evidence that Berle—who notoriously used others’ jokes—said it first.
 
       
21 December 1976, Centre Daily News (State College, PA), “Good Evening!,” pg. 1, col. 3:
DELAY: If evolution really works, Ed Dussault asks, how come mothers still have only two hands?
   
Google Books
Quote Unquote
By Lloyd Cory
Wheaton, IL: Victor Books
1977
Pg. 102:
If evolution works, how come mothers still have only two hands?
(ED DUSSAULT)
   
23 February 1977, The Mercury (Pottstown, PA), pg. 39, col. 4 ad:
“If evolution really works how come mothers still have only two hands.”
(Edward James Oldsmobile.—ed.)
 
15 July 1977. The Daily Standard (Sikeston, MO), pg. 2, col. 6:
A DARWINIAN FLAW?
If evolution really works, how come mothers still have only two hands?
Ed Dussault
 
13 May 1979, Sunday Star (Toronto, ON), pg. A3, col. 6:
If evolution really works, how come mothers have only two hands?
     
Google Books
Meditations for New Mothers
By Beth Wilson Saavedra
New York, NY: Workman Publishing
1992
Pg. 265:
If evolution really works, how come mothers only have two hands?
ED DUSSAULT
   
Google Books
A Mother’s Love:
Reflections and Memories
By Jane Resnick
New York, NY: Smithmark Publishers
1995
Pg. ?:
If evolution really works, how come mothers still have only two hands? - ED DUSSAULT
   
Google Books
Don’t Stop Laughing Now!:
Stories to tickle your funny bone and strengthen your faith
By Barbara Johnson, Ann Spangler and Shari MacDonald
Grand Rapids, MI: Zondervan
2003
Pg. 157:
If evolution really works, how come mothers only have two hands? -Milton Berle
 
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JJ
@jjmac
just ordered my mom some flowers.  barely in time.  If evolution really works, how come mothers only have two hands?  ~Milton Berle
7:26 PM - 6 May 2008
   
Google Books
The Snark Handbook: Parenting Edition:
Morning Sickness, Potty Training, Rebellious Teens, and Other Joys
By Lawrence Dorfman
New York, NY: Skyhorse Publishing
2013
Pg. ?:
If evolution really works, how come mothers only have two hands? —MILTON BERLE
 
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@CourtenayTigers
“If evolution really works, how come mothers only have two hands?” -Milton Berle
#HappyMothersDay
4:10 PM - 12 May 2019