Friday, January 6, 2012

Sperm, Nipples, & Guts: Top 10 Stories from the Evolution of Beef (pt. 1 of 3)

Since I had the idea to shift this blog into a purely evolutionary perspective, I have been awash in a tidal wave of research and perspectives on the matter.....Where could I possibly start?
How about with the absolute Top Ten stories from my personal Beef files! 
These are the stories that got me hooked on thinking this way about meat and agriculture, and the stories that I hope will show you another universe within the world of the bovids.
The following short stories are in rough chronological order, not based on preference. They are a preview of whats to come, intended to offer a more comprehensive big-picture, a road map, before we dive deeper into these, and other stories from the real-world mythology of meats.
There are many questions and unkowns in the field of evolution, and while any of the details contained herein could shift or change with new evidence - one truth will remain absolutely eternal - that of the unbroken chain....

From story #1 about our spermoid-forefathers, to story #10 about our own very own personal experience of evolutionary Amazement; there is a direct and unbroken chain of cooperation and compassion, triumph and success.

1. Sperm
Sperm Cells 
from Wikipedia
Neocallimastix Fungi from a Bovid Gut 
by Daniel Wubah
Did you know the old "What came first- the Chicken or the Egg?" bit, is not actually a parable, but an entirely answerable question? The answer, of course, is Sperm! Mycologist, Paul Stamets is famous for describing humans as having descended from Fungi. Pointing to the relatively recent discovery of the Opistokonta Super-Kingdom. This new trunk on our global family tree links the kingdoms of Animal and Fungi as far more connected to each other than to any of the other known taxonomic kingdoms. More simply put, after the first emergence of life, bacteria appeared, than later plants developed off of this line. Eventually these "opistokonts" split-off from plants into a genetic line that would eventually come to form every living animal and fungi existent today - including you, me, and that swiss-mushroom cheeseburger I ate for dinner last night. So if we (and cattle as well) are related to Fungi- what was our Last Common Ancestor like? What features did we share in common with these original opistokonts? Odd as it may seem - the two things that can actually best help us understand this are Sperm cells & Cow Stomachs.... 

2. Nipples
Angus Cow Nursing her Calf - After 350 M years of Evolutionary Development
Photo ©
The first baby-bottle nipples were fashioned from the teat of a dairy cow. Milk itself seems to be a universal symbol for kindness & generosity - yet from where did these flowing udders emerge? For this shocking tale we have to travel back some 350 million years ago! Back to the time of the Synapsids, some of the very first land-roaming reptilian-like monsters to escape the darkness of the sea. No - these ancient lizzardesque synapsids did not sport the credentials to enter the biological dairy business. Rather, they offered their youth something much more fascinating at the time.....stinky butt sweat. While the bio-chemical and functional reasons are argued, scientists generally concur that the mammary glands and nipple structures in modern mammals (cows and humans alike!) developed over the eons through infantile preference for the exudates (sweat) from one or more sub-dermal glands in our most reptilian of grandparents (butt and stomach sweat). That is to say - there is a direct and unbroken chain between the calves and babies that suckle the teats of today, and the dietary choices of our deepest of reptilianoid ancestors. And then there's whole this part about the kangaroo baby......

3. Guts
The Chevrotain - a Primitive Ruminant
Photo: Wikipedia
Here's a chevrotain - a tiny "mouse deer", and member of the Tragulid family. While the chevrotain is a modern creature, she is as close as we might get to the most primitive last common ancestor of cows, sheep, goats, bison, and all their wild ruminant relatives. Yet the very first ruminants did not ruminate - that is - the most ancient of cattle ancestors were not yet able to digest grasses and chew a cud as their modern descendants do so gracefully.

How and what a cow decides to eat, has been shown be an incredibly complex decision. These daily decisions are made on a complex of biochemical and cultural feedback mechanisms (yes - animals have culture too). Yet, while you could say the same of humans, we seem to not be very good at picking our own diets anymore (at least many of us). Simply put - cattle and humans pick their foods through very different mechanisms. Humans now have fully cognitive, and ever more so, fully socio-political and economic systems for regulating and selecting our diets. So how did this happen? How exactly did we diverge from our last common ancestor with cattle- the mole-like boreoeutherians of some 100 mya? The "guts", or digestive systems of both cattle and humans form pivotal functions in the interwoven narrative of contemporary evolution - join me in future posts to see these complexities unfurled!

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