Owning a cattleranch gives me some insight into such matters. Cattle herds
are usually surrounded by fences and are virtually entirely dependent on
water sources managed by man. Situationally, a few pure bread cattle might
be in a large enough well watered area to survive until the fencing becomes
ineffective to hold them into their micro environment. This would have to
occur rapidly because population increase in the fenced in island
population would be rapid until the grass available would be used up.
(roughly doubling every year). Inbreeding of these island populations
would become an issue as well as predatory problems as more mobile
predators (reintroduced wolves) would also nibble away at the populations.
In cold climates, almost all cattle herds are dependent on extra man
provided feed to make it through the winter so their survival rate would be
very low as well as high calf mortality rates. Overall, these problems
might be overcome by very small groups in very large grass pastures of
hundreds of square miles in more temperate climates that I live here in
northern wyoming. Herds stuck in summer pastures with pine trees will
spontaneously abort due to eating pine needles in the winter (turpintine).
In domestic cattle, the selection process would be against features we
desire such as large muscle groups with no horns and for features that
promote survival and early reproduction in the wild. Resistance to
parasites and diseases that we currently vaccinate and dip for would be
selected for. I personally doubt that most herds would survive the first
winter and most would not survive the 20 years for the fences to fall down
to effectively make the region open range. When left to their own
devices, Bulls impregnate yearling cattle and as a result most of the
yearlings would die without human intervention during birthing. Aggression
in Bulls would also increase through selective pressure causing some
decrease in diversity. Bulls still can't impregnate many more than 30 or
so cows a year. The number of bulls would rapidly escalate due to the lack
of castration during yearly brandings and fights would increase. The one
thing they do have going for a long term survival is that there are just a
huge number of bovine individuals in every ecosystem in the world. Some of
them would survive but the population would certainly bottleneck for
decades and suffer inbreeding for many more. The eventual result may
resemble those of Chetah genetics (the whole population may have originated
from one pair), or even human genetics (which seems to have undergone a
bottleneck or two also.). . Typical cattle are even too stupid to paw at
the snow to get to the grass under the snowcover. Horses and Bison have
that figured out. It is more likely that the already well adapted wild
bison will come back from areas like Yellowstone. Any cattle interbreeding
with bison will have a better chance of survival than pure breeds.
Conclusion: they will survive probably assuming that what ever kills us off
leaves all other mammals alive
Buy american beef! Angus diet and all that.
Frank Bliss
MS, Biostratigraphy
Weston, Wyoming
www.cattleranch.org
On Oct 16, 2004, at 8:21 PM, Dr. Darrin T. Milne B.Sc., D.C. wrote:
In the fictional book 'Evolution' by Stephen Baxter, he writes about a
possible future (post-homo sapiens) where huge herbivores roam the earth
which are the descendents of goats and cows (as well as rabbits now that I
remember). While this is hypothetical, I was always under the impression
that, if humans were to become suddenly extinct, certain extant
domesticated
species (specifically the cow) would follow because of their dependence on
man. Does anyone have a idea if domesticated cows could become feral and
ultimately survive in the absence of man?
Darrin