It is forecast to be Partly Cloudy at 10:00 PM PST on December 25, 2014
Partly Cloudy
Home » Santa Clarita News » Environment » SCV Outdoor Report » SCV Outdoor Report: Armpit Effect…

SCV Outdoor Report: Armpit Effect…

By Wendy Langhans

Have you ever noticed how
many different type of deodorants there are? 
I did a quick search on and found 371 different results, ranging from
clear gel to ultramax.  Some have no
scent while others make you smell like a flower garden.  Some even give you the "easy-going, guy-next-door
effect" (whatever that is).


But in the natural world,
smelly armpits (or other parts of the body) can be a good thing.  That's how some animals distinguish unrelated
neighbors from unfamiliar kin.  Knowing
your kinfolk can be useful when searching for a mate, or when you want to do a
favor to a family member (and thereby increase your own chance at


Biologists have two
theories as to how this scent recognition works:


Theory A (Childhood memory):  Babies learned the smell of their mother and
littermates and remembered this smell throughout their life. 


Theory B (Armpit effect):  Animals sniff themselves and then compare
their scent their neighbors'; an animal who's smell resembles your own is a
relative.  Biologists refer to this as
"self-referent phenotype matching" and informally as the "armpit effect". 


In a recently published
study, an ecologist tested these two theories on Belding's ground squirrels.  These
small mammals live in the Sierra
Nevada and Cascade mountains, hibernate during the cold winter, and are born
into litters of brothers and sisters. 
For protection, females live in a close-knit cluster of relatives, so
knowing who is and is not part of your family is necessary for survival.


As an experiment, they created foster families by switching babies
at birth.  These babies grew into adults,
who then went into hibernation during the winter.  After awaking from hibernation, these ground
squirrels did not recognize their foster family, but did recognize their
relatives.  Here we have evidence
suggesting the "Armpit effect" is at work.


And since Belding's ground
squirrels and California ground squirrels come out of hibernation in the spring to mate, I'm
sure there will soon be a whole lot of sniffing going on.

California Ground Squirrel in Towsley Canyon.




Upcoming Outdoor Events: 


Saturday, March 21, 8:00-10:00
AM.  Morning Bird Hike in Towsley
Canyon.  Towsley Canyon is a year-round home for birds. 
They like our Mediterranean climate, the local bounty and the California sunshine. 
Bring your binoculars and meet at the entrance.  Heavy rain cancels.  For map and directions go here.

Sponsored by the Mountains
Recreation and Conservation Authority.


Saturday, March 21, 10-12 AM.  Wildflower hike at Elsmere

Heavy rain cancels.  For map and directions go here.  Park at the
entrance to Whitney Canyon.

Sponsored by the Mountains
Recreation and Conservation Authority.


Saturdays, February 28, and every Wednesday, 8:00 AM. 
Trail Maintenance Volunteers at Towsley

Come join our trail
maintenance volunteers for camaraderie and a heart-thumping workout.  For
more information contact Steve Ioerger at 661-291-1565.



You can listen to stories
like this every Friday morning at 7:10 a.m. on "The Hike Report", brought to you by your hometown radio
station KHTS (AM1220) and by the Mountains Recreation and Conservation


For the complete MRCA hike
and activity schedule and for trail maps, click here or go to

SCV Outdoor Report: Armpit Effect…

Leave a Reply

Your email address will not be published. Required fields are marked *


You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>

About hometown