There's no such thing as a blue butterfly

Hi BBC Earth! Here's my video for the #BBCEarthPresenterSearch. I'm an evolutionary biologist finishing my PhD in fruit flies and behaviour at the University of Oxford. I've been making biology and science videos online for 5 years and would love to use the platform of BBC Earth to share my love of the natural world with a broader audience.

A few things I couldn't fit into the video:
- The only land animal that has managed to make a true blue pigment is the obrina olivewing, but it has more of a blue stripe rather than what I would call a "blue butterfly" :P The turaco and similar birds have also managed to make a true green pigment rather than resorting to the more common method of overlaying yellow pigment and blue structural colour.
- You can also pour ethanol on the wing and it will fill up the gaps between the branches and again the butterfly will turn brown. If you grind up the wing with a pestle and mortar, you'll be left with a brown, not blue, dust (and no more butterfly!)
- If you have green eyes, it's a mix of the blue structural colour and a small amount of melanin (brown pigment) mixing together to make green. Because structural colour works by manipulating the reflection of light, blue (and green) eyes can appear to change colour in different lighting!
- Thank you to the Stratford Butterfly Farm for the Blue Morpho butterfly. It died of natural causes.

Me:

[SallyLePage]

It's been 6 months since my last video, so here's a one minute video to tide you over for the next 4 months! Don't say I'm not generous to you!
Seriously though, thank you for being so patient. As many of you know, I'm not making any videos at the moment as I'm in the final throes of writing up my PhD thesis, which I'll be submitting in October this year (eek!). After that I'll be going into science communication full time as a freelance YouTuber and presenter. I've received so many tweets and messages of support while I've been writing up and it really is incredible to know you're happy for me to focus on the last few months of my studies. So thanks, and see you on the other side! :)

[willemvandebeek]

Good luck with getting the position; hope you get it! :)

[Joel-hwsl]

The Olivewing butterfly has a blue pigment

[piplupcola]

I hope you get the part Sally! I would love to see you in a BBC documentary! 😊

[Kassidar]

Minor correction:
Colourless eyes, such as in the case of albinism, appear pink. This is from the red retina behind them. Blue eyes do have a little melanin in them.... that's why you can get different shades and hues of blue eyes.

[BioBush]

Awesome presentation! Structural coloration is one of those commonplace miracles that nobody knows about. You convey expertise and a happiness to share your knowledge. Good luck!

[chesterrobinson]

As a fellow brit who grew up being utterly flabbergasted by the amazing documentary series put out by the bbc (walking with dinosaurs and blue planet were my faves) it would be absolutely amazing to see such a bright, enthusiastic and passionate presenter such as yourself take up the mantle for the next generation of the beeb's science entertainers and help enfuse passion within the upcoming generations for the wonderful world surrounding us in all it's intricacies!

[scbtripwire]

Beautifully spoken and very well presented, I hope you get it! Charismatic people are so important to the spreading and appreciation of knowledge!

[DeskOfKidAdorable]

This was certainly a pleasant birthday surprise! Don't forget to look back and reflect on the journey as you enter the doctoral home stretch; then embrace the beautiful mess of a life in transition.

[RyanDB]

Good to see you again, and I hope that the BBC snatches you right up! :)

Best of luck with your thesis, too. I've spent the last year on a master's project in chemistry, so you have my sympathy

[rbphilip]

It's October! Hopefully the PHD thesis went over well, as the rest of us knew it would! The world desperately needs more Sally Le Page videos!

[itsamemari]

You're videos are always wonderful. Thank you

[crossxcats]

Obrina Olivewing is the only butterfly that has miraculously conquered the blue mystery.

[skarrambo]

As a nanophysicist, I approve of this biology video haha - great work, love telling people with blue eyes that they have skies in their eyes!

[christianwuethrich]

The color of the wing changes with the angle of view, at 00:29 it looks more purple than blue.

[ordinaryorca]

Though it should be added that butterflies of the genus Nessaea do make uniquely among all animals a blue pigment, but they are only partially blue other animals with this ability are mandarin fish and the psychedelic mandarin but those are the only ones I know of

[shaygeange]

Obrina olivewing's have the worlds only true blue pigment for butterflys.The rest it's just the light that escapes the scale structures that make up butterfly wings.

[pauls]

regardless if it's by pigmentation, prismatics or selective reflection, the result is perceived blue wavelengths around 450 nm or so

[DanielFoland]

Sally gets my vote for BBC presenter. 2019! Let's make it happen

[oyst]

Thank you for the video and good luck! Thank you for being awesome!