New Scientist 14Mar2020

54 | New Scientist | 14 March 2020

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KEITH MORRIS/ALAMY

Nuts 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 are

carnivores. 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 talked

about 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, Spain

Great fleas... How small does an animal or insect have to

be before it can’t have fleas, mites or lice? Nina Dougall,

Malmsbury, Victoria, Australia

Why do some people

sneeze many times in

a row and others don’t?