Gender Differences

/ in Know Your Moths by Marek

An aerial look at the gender differences between moths.

Top down shot of a male and female Common Quaker moth, highlighting the sexual dimorphism in the length of the receptors on their antennae
His and Hairs

January and February due to the weather in the UK are always likely to be unpredictable with regard to the number of moths seen, if any.

This has been the case for me the last couple of months which has given me the opportunity to finally catch up with the backlog of images from last year.

No sooner had I finished this mammoth task when temperatures increased, and we finally began to attract some moths to the trap so I can start creating a new back log of images for next year.

The highlight for January for us was an Oak Beauty which paid a visit giving me the opportunity to play around with my new bridge camera.

Top down shot of an Oak Beauty moth
A bridge not far

I will not be using this camera for images at home as it was purchased mainly for taking out into the field to record day flying moths and butterflies which are rather difficult to find at the moment, but I need to get some practice in. February brought us only our second Early Moth record which we had seen for the first-time in 2017 so it was time to begin recording images again in earnest.

Yesterday morning produced our best results this year with two Common Quakers, one Early Grey and a single Light Brown Apple Moth.

Although I have good examples of all these moths on the site, I can never resist the temptation of taking more shots just to compare the results and I suppose to keep my hand in.

Also, good progress has been made by my son with the website update which includes the facility of viewing different variants of moths, so I am in the process of recording images to populate that field.

I took full sets of pictures of both the Common Quakers and during comparison was drawn to the substantial difference in their antennae.

As eluded to in a previous post, male moths’ antennae are used to detect the presence of females using scent receptors.

The receptors are so sensitive that males can detect a female up to distances of six miles, so I have read.

It suddenly dawned on me that maybe that the difference in antennae was a way of determining the sex of this species of moth.

So, I began to do some research on Google to see if the internet could provide the answer to my question.

But the best I could come up with was comments like ‘put it in a room with a telephone and a can of beer. if it lands on the beer its male, on the phone its female.’ and ‘the male’s the one with mothballs’ which although humorous wasn’t really what I was looking for.

I had to look elsewhere for the answer but now have it on good authority that my suspicions were correct as portrayed above.

As I was concentrating so much on the Common Quakers the Early Grey got bored sitting around waiting for some attention and decided to start his exercises prior to departure.

Front shot of an Early Grey moth, its wings a blur of movement
Getting ready for lift off.