This document discusses theories around how and why human intelligence evolved. It suggests that as humans developed tool-making skills, they were able to scavenge meat and nutrient-dense animal offal more efficiently. Eating these high-calorie foods allowed human brains and bodies to grow larger while reducing the time spent chewing. Over generations, natural selection favored smaller jaws and teeth as physical traits were no longer as important for survival. The document also notes that modern human brains are larger relative to body size than most other species and have doubled in size since early humans emerged.

1. IS IT HEALTHY TO
EAT MEAT?
L E S S O N 1 : I N T R O D U C T I O N

2. LESSON OBJECTIVES:
• Introduction to
Caroline
• Understanding how
humans have evolved
compared to other
species
• Understanding how
eating offal led to the
development of our
brains and skills
• Connect with us on our
social platforms to
become part of the
Wilderculture
community
This Photo by Unknown Author is licensed under CC BY-SA

3. A LITTLE BIT ABOUT
ME…
Hi, I’m Caroline. I specialise in ancestral health with a
particular interest in nourishing animal foods. I started
my career in environmental conservation as a National
Park ranger and then studied sustainable farming
practices whilst co-managing a diversified 600-acre hill
farm in the Lake District.
I am now a Savory Institute Professional Educator in
Holistic management and I work with farmers and food
businesses to help them adopt a more regenerative
approach. I specialise in ancestral health and primal
living. I am looking forward to guiding you through
this course and assisting you on your journey to
deciding is it healthy to eat meat? Caroline Grindrod
Wilderculture expert.

4. LET’S GET
STARTED

5. EAT YOURSELF
AND THE LAND
HEALTHY
To start off and help you
develop a base
understanding of this course
please click on the video to
view my speech at the 2016
Every Family Needs a Farmer
Conference.
You can also access the
video directly on YouTube
at:
https://www.youtube.com/w
atch?v=Mjo7Q4V2vdU
Screen time: 34 minutes

6. ARE WE CHIMPS?
Molecular techniques which
reveal similarities in DNA show
we are between 95 and 98.5
percent genetically identical to
chimps!
This divergence from our cute
cousins happened about 6
million years ago, so chimps
and humans have both had
quite some time to evolve in
different directions. In this time
Homo sapiens brains have
increased 300%.
This Photo by Unknown Author is licensed under CC BY

7. ARE WE THE MOST INTELLIGENT
SPECIES?
Modern human brains take up
approximately 2 percent of our body
weight, but use about 20 percent of our
energy; so what happened to our bodies
that they can dedicate so much energy to
powering our big old brains?
When you compare the size of a human
brain against an elephant brain but also
consider how much larger an elephant is
than a human it becomes apparent that we
have evolved to become more dependant
on brain functionality.
If we compare humans to most animals,
human brains are bigger as a percentage of
body weight. Our brains have even
doubled in size since the first appearance if
our species about 2 million years ago. This Photo by Unknown Author is licensed under CC BY-SA

8. THEORIES
W H Y H AV E W E E V O LV E D TO B E C O M E
S U C H D O M I N A N T A N D S U P P O S E D LY
I N T E L L I G E N T S P E C I E S ?

9. 1.
One theory that could explain it, is the
metabolically hungry liver and
gastrointestinal tract shrunk as the
brain size increased. It can take some
primates 80% of their daytime activity
sourcing, eating and digesting their
low calorie plant food. Having a
smaller gut requires that the main
food source comes from high nutrient
density, high calorie but easily
digested foods.
This Photo by Unknown Author is licensed under CC BY-SA

10. 2.
Aiello and Wheeler in their ‘expensive tissue
hypothesis’ suggest that it was the nutrient
dense meat and offal of animals that was the
key food in the evolution of our large brains.
Types of offal include: liver, kidney, tripe,
gizzards, heart, tongue and intestines.
This Photo by Unknown Author is licensed under CC BY-NC-SA
This Photo by Unknown Author is licensed under CC BY-NC-ND

11. SO WHAT DID OUR ANCESTORS DO?
It could be that our very earliest
ancestors actually didn’t do the
killing themselves, rather our tool
making and collaborative social
skills gave us access to the very
best animal sourced nutrients.
Some of the earliest found
human-made tools date back 3.3
million years and don’t appear to
be suitable for hunting.
This Photo by Unknown Author is licensed under CC BY-NC-ND

12. WHAT WERE THEIR TOOLS FOR?
The tools identified were most likely used
for slicing through tendons and
ligaments to remove flesh from bone and
percussion tools for opening long leg
bones, jaws and skulls. It’s perfectly
possible and probable that organised
groups of human scavengers evolved
techniques for keeping hyenas away
from carcasses left by big cats,
intercepted carcasses hung by leopards
in trees, and took advantage of the
natural deaths that occurred by accident
in the vast herds of wild ruminants that
would have been walking the earth at
that time.
This Photo by Unknown Author is licensed under CC BY-SA

13. LEFTOVERS?
In a fascinating article in the New
Scientist a live experiment of simulating
passive scavenging for 7 months in a
Kenyan nature reserve is detailed. By
observing how much meat and marrow
was left on carcasses after the predators
had their fill it was observed that as
much as 15kg of meat scraps were still
available on a zebra; this equates to
60,000 calories! If only we were so good
at reducing waste these days.
Of course, the type of food that was left
is likely to be very high in nutrients and
would include brain and bone marrow.
This Photo by Unknown Author is licensed under CC BY-ND

14. A SUPERIOR SPECIES
It seems our early knife skills could be one of the
reasons we thrived as a species and don’t have large
floppy muzzles or talk in chimp! Being able to cut meat
into smaller more easily chewed pieces enabled more
calories and nutrients to be digested in a shorter period
of time allowing greater gaps between meals for
hunting, rest and – err – breeding!
This Photo by Unknown Author is licensed under CC BY-SA
This Photo by Unknown Author is licensed under CC BY-SA

15. WHO’S THE QUICKEST
EATER? • Both tools for slicing and
pounding the meat allowed us
to reduce the ‘chew time’ by
around 17% – the equivalent to
about 2.5 million chews per
year. According to evolutionary
anthropologist Daniel
Lieberman at Harvard, a
reduction of this significance
could easily been enough to
allow early members of our
genus Homo to evolve smaller
teeth and jaws. Our closest
relative the chimpanzees for
example spend 6 hours a day
eating fruit, fibrous plants and
occasional protein and gorillas
can spend up to 10 hours a
day.
This Photo by Unknown Author is licensed under CC BY-SA

16. NATURAL SELECTION DEVELOPMENTS
As our lives became less dependent
on endlessly chewing tough plants
and sinewy wild game meat, big
teeth and long jaws stopped being
necessary to our survival—natural
selection could start favouring other
traits instead, perhaps ones
conducive to the development of
speech?
This Photo by Unknown Author is licensed under CC BY-NC-ND

17. SUMMARY
WHAT HAVE WE LEARNT?
This Photo by Unknown Author is licensed under CC BY-NC-ND
• We are between 95 and 98.5 percent
genetically identical to chimps!
• Our brains have even doubled in size since the
first appearance if our species about 2 million
years ago.
• Offal of animals are a key food in the evolution
of our large brains.
• Our tools skills allowed us to reduce our ‘chew
time’ by around 17%.
• Natural selection started favouring traits such
as the development of speech.

18. JOIN OUR COMMUNITY
Join our community across your social media to keep
informed about new articles, contests and to contribute
to our discussions surrounding ecological restoration.
Use the icons below to connect with our channels.
This Photo by Unknown Author is
licensed under CC BY