54 | New Scientist | 14 March 2020
Want to send us a question or answer?
Email us at [email protected]
Questions should be about everyday science phenomena
Full terms and conditions at newscientist.com/lw-termsThe back pages Almost the last word
KEITH MORRIS/ALAMYNuts for apples
A squirrel surprised us this autumn
by picking apples from a tree and
placing one each in hanging baskets
around our garden, as well as
putting two on top of the fence.
Is this unusual behaviour for a
squirrel?
James Stansfield
Winchester, Massachusetts, US
A few winters ago, I came across
some stale ice cream cones at
the back of a cupboard and put
them out in the garden, in case
any animals might want them.
Soon after, I saw a squirrel placing
them on shrubs all around the
yard. As it was nearly Christmas,
this seemed very appropriate.
The squirrel carried each cone by
holding one edge of the open top
in its mouth, so it appeared to
have a large, pointed snout.
Kay Bagon
Radlett, Hertfordshire, UK
I wonder whether this squirrel
is just playing a game by picking
apples from the tree and placing
them in pots and on the fence.
This week, I watched with
growing annoyance as several
squirrels perched in our magnolia
tree, pulled off the flower buds
and merrily threw them on the
ground. They then repeated the
operation on our camellias.
The editor of this page,
Julia Brown, writes:
We have looked into this, and
the most likely answer is that
the squirrel is caching the apples.
Squirrels are known to store nuts
by burying them, but they are
omnivores that also eat apples,
insects and much more besides.
We have often seen squirrels in
London burying their hazelnuts
in plant pots, so maybe the apple-
caching squirrel has decided that
hanging baskets are a good
location for storing apples.
Contrary to popular belief,
squirrels have good memories
and well-developed strategies for
food storage. A recent study by
Mikel Delgado at the University
of California, Davis, found that
eastern fox squirrels didn’t bury
nuts randomly, but instead had a
system for organising where they
were buried based on the species of
nut and where it was foraged from.
And if they think another squirrel is
watching them, they will even dig
a hole and pretend to bury a nut,
then cover over the hole and bury
it somewhere else.Awful eaters
Foxes have the most repulsive
smell, alive or dead. We often see
dead foxes on our farm and they
just decompose in situ. So, does
anything eat foxes?C. W. G. Angus
Wormit, Fife, UK
Some years ago, I noticed a
dead fox lying in a fenced area by
Lochan na Lairige in Perthshire. It
looked as if it had recently fallen
from the cliff above.
Sexton beetles were already
burrowing into its fur. These
beetles and their larvae arecarnivores. I visited the spot
about two months later and found
no evidence of the fox.Luce Gilmore
Cambridge, UK
Foxes are sometimes eaten by
roadkill enthusiasts. The taste is
said to be challenging. There are,
by the way, vegans who are open
to eating roadkill because these
animals weren’t deliberately
killed. Waste not, want not!Come clean
Is there a difference between
shampoo and shower gel and,
if so, what is it? (continued)Stuart Sjalund
by email, no address supplied
I enjoyed the previous answers to
this question, but they only talkedabout surfactants. There are other
considerations.
One is pH. The pH of shampoo
can vary, but I have found that
the higher the pH, the stronger
the cleaner. Sodium hydroxide,
the workhorse of any shampoo
or shower gel, helps control a
product’s pH level. While it is
true that shampoo can be used
as shower gel, the reverse can also
be true, depending on the pH.
I make my own shampoo and
shower gel very inexpensively. For
shower gel, I use off-the-shelf soap
and detergent – I am not interested
in reinventing the wheel – plus
sodium hydroxide, and this
works very well. This results in
almost complete body oil removal
and a very high-quality body
disinfectant. When I use this daily,
deodorant sprays are no longer
needed. My body oil is replenished
continuously as is required, so
there is no problem for me here.
Please remember, though, that
sodium hydroxide is extremely
dangerous if mishandled. It is fine
when properly diluted in water,
but if in doubt, use less.
I also make shampoo using
a soap and detergent amalgam
with a pH of around 10. But there
is no set recipe and you can vary
the quantities of these to find a
formulation that you like.Victor Cheetham
Bolton, Greater Manchester, UK
On a related subject to this
question, I wondered about
soap. I am an ardent believer
that soap is better than shower
gel because, in addition to its
surfactant properties, soap is
also alkaline and will dissolve
some dead skin, thus improving
the cleansing process. Am I
right or just deluded? ❚This week’s new questions
Bless you Rather than sneezing once or twice, some people
do so again and again. My partner often sneezes 20 or 30
times in succession. Is this common, and is there any
explanation? Kate Wreglesworth, Granada, SpainGreat fleas... How small does an animal or insect have to
be before it can’t have fleas, mites or lice? Nina Dougall,
Malmsbury, Victoria, AustraliaWhy do some people
sneeze many times in
a row and others don’t?