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scientists who study our planet's past
often have to piece together some pretty
disparate clues fossils artifacts and
other lines of evidence can often be few
and far between so you can imagine how
handy it would be to have an animal that
collects clues from its environment and
stores them away in a nice convenient
spot meet the rock hyrax of africa a
little animal that scientists love
because it preserves pieces of the past
in piles of poo these furry little
mammals live in and among rock crevices
it may look like rodents but research
has found that their closest relatives
are actually elephants and manatees rock
hyraxes live in large colonies and those
colonies have developed the peculiar
habit of using what are called communal
latrines which is exactly what it sounds
like a designated spot that everyone in
the colony uses for going to the
bathroom these rocky toilets tend to be
located in safe sheltered areas so a
single latrine can last quite a while in
some cases a latrine might be used by
the same colony over hundreds of
generations forming a heap of waste that
can be used for centuries the end result
is a mitten a multi-layered collection
of fecal pellets and a substance called
high ratio or the dried remains of hyrax
urine which is something that was worth
giving a name to because here's the
thing
the hyraxes are only trying to keep
their colony clean but they unknowingly
capture plant and animal remains from
their nearby environment and preserve
them in a time capsule which makes these
poop piles a goldmine for researchers
normally when we want to learn about how
an ecosystem has changed over time we
look at biological and chemical evidence
preserved in fossils ice cores or
limestone cave formations but in certain
dry rocky parts of Africa those types of
evidence are pretty rare hyraxes however
are common and so is their excrement
which has led to a seriously impressive
body of hyrax waste literature not only
do hyrax middens preserve environmental
data from the time the waste was created
they
often do so in convenient chronological
layers each time a hyrax lays down a
fresh coat of urine it seeps across
rocks and around the poop pellets and
when it dries it cements into a new
layer of hi ray cm crust in some places
hyrax mittens can be over a meter thick
and several meters across and under the
right conditions a mitten can become
petrified and persist long after the
higher x colony has moved on they can
contain millennia of environmental
history and the oldest known hyrax
mittens preserved waste that's 50,000
years old generally hyrax mittens
contain a lot of plant material since
that's what the little guys eat and
those plants can tell us a lot
especially about the climate and growing
conditions that existed when they were
eating like a 2010 study that looked at
an increase in leafy plants relative to
grasses in two mittens over the past
10,000 years or so this adjusted the
climate may have been drying out enough
to make it hard for hyraxes to find the
lush tasty grass to eat and there's more
in those mittens than just the plants
hyraxes ate hauling grains are famously
durable and they can be preserved in
mittens when they drift in from the air
or are carried on hyraxes fur in a 2011
study researchers collected mid-and data
from southern africa spanning almost 20
thousand years of history this time
looking for ancient pollen the pollen
revealed changes through time in faint
boss scrubby vegetation that makes up a
unique type of plant ecosystem in
southern Africa the pollen record showed
that past shifts in climate affected
lowland faint boss more dramatically
than the mountain varieties data that
might help researchers protect these
endangered plants in the future research
in hyrax middens has uncovered not only
plant remains but also ancient DNA from
animals that share the hyraxes habitats
and microscopic remains of charcoal that
reveal local fire history and all of
this data can be combined with other
information to reconstruct the history
of Africa and even of our own species a
2018 study compared climate information
from hyrax mittens to archaeological
records of human activity in South
Africa over the last 20,000 years or so
the data showed that as the regional
climate grew drier coming out of the Ice
Age and large prey became harder to find
local humans
changed their survival strategies in
many ways they became less picky about
their resources and went after more
small animals like hares and tortoises
and they made their tools out of lower
quality more common types of rock these
changes reflect the amazing adaptability
of our species in response to changing
conditions and this information is
brought to us by the latrina legacy of
the hyraxes that lived alongside our
ancestors Africa is a continent of
particular importance to the history of
our own and many other species and while
there are mitten making mammals on other
continents its hyraxes that provide a
unique insight into Africa's past
hyraxes and other midden building
species have been creating ecological
time capsules for tens of thousands of
years
they're the unwitting field assistants
for today's scientists it might not
sound like the most glamorous job
digging through thousands of layers of
an ancient latrine but for scientists
seeking to understand our world's
history there's nothing better than a
bit of preserved hyrax waste but you
don't have to go digging through higher
x mittens just to learn stuff for the
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