"To get from one adaptive peak to another" - Sewall Wright
"It didn't gradually cross the road, it saltated to the other side" - Richard Goldschmidt
"The chicken crossing the road is the canonical example of a non-adaptive consequence of the Dodgers leaving Brooklyn, which reminds me of an unfortunately often overlooked manuscript illustration from 1302, which demonstrates the inherent and ineluctable logic of punctuated equilibria, which, as Darwin himself said, nicely illustrating my point, brings us back to the question with which I started this essay of the chicken crossing the road" - S.J. Gould
"It transposed to the other side" - Barbara McClintock
"To maintain its internal milieu" - Claude Bernard
"It was directed across the road by aliens who wanted to start a chicken farm on the other side" - Francis Crick
"To change paradigms" - Thomas Kuhn
"To disprove the hypothesis that chickens could not cross roads" - Karl Popper
"To bond to the other side" - Linus Pauling
"The wisdom of the chicken's body" - Walter Cannon
"It was selfish" - Richard Dawkins
"Any similarity between chickens crossing roads and poulets crossing rues is purely coincidental" - Robert Gallo
"I have utmost faith that the chicken crossed the road if it said it did, but, of course, I had nothing to do with it if the chicken did not cross the road when it said it did" - David Baltimore
"To escape a meteorite impact" - Walter Alvarez
"To become an organ of a larger chicken" - Lynn Margulis
"To change it's proportions" - D'Arcy Thompson
"One chicken does not a road make" - Aristotle
"It crossed he road to observe the F1 offspring" - Gregor Mendel
"The natural tendency to increase on one side of road had selected for the tendency to travel to the other, less populated, side of the road" - Charles Darwin
"Gallus gallus. Via roadus" - Carl Linnaeus
"Never mind the why and wherefore, chickens cross roads and therefore" - W.S. Gilbert
adapted from David A. Spencer (Perspectives in Biology and Medicine 1997)
Continued by the young Zoology PhD's in Oulu (by EH...)
"It was trying to avoid a predator" - Arto Huhta
"It was bred in captivity - and therefore showed anomalous behavior" - Ahti Putaala
"To change to a thermally more favourable environment" - Liisa Peltonen
"It was hoping to become a dominant member of the flock on the other side" - Kimmo Lahti
" To guard it's mate" - Petteri Welling
"It was looking for food with a higher concentration of nutrients" - Tuija Liukkonen
"It was replacing shivering thermogenesis
with motor activity" - Kyösti Marjoniemi