Insect Mimicry & Conservation with Dr. Francis Gilbert – 8/10/2012

7th October 2012

Insect compound eyes and antennae
It’s the middle of summer and you’re sat outside at your BBQ with a cold can of cider loving life right now … until you take your next drink and get stung on your tongue by THAT BLOODY WASP THAT WON’T LEAVE YOU ALONE. Ok, so that hasn’t happened to me, but it could…

Found on every continent, and even under the ocean, insects are everywhere around us whether we like it or not. It is estimated there are up to 10 million species of insect alive today on planet Earth.

Insects are part of the Arthropod phylum, and as such have an external skeleton and jointed limbs. All insects have six legs, and are the only type of invertebrate which has evolved the ability to fly.

Today’s guest is Dr. Francis Gilbert is particularly interested in the evolution of life histories and mimicry in insects. We will be talking about mimicry in insects, insect-plant relations and conservation.

Tune in to find out more!

Natural Selection

This is competition between those within a species rather than competition between species. This is one reason trees grow so large, the taller ones gather the most light and convert the most energy and are the strongest, this leads to them surviving longest.

Mimicry

Mimicry is one of several anti-predatory devices found in nature. It does exactly what it says on the tin, by mimicking in color, form, and/or behaviour one species takes on the appeareance of another and in doing so, the mimicker acquires some survival advantage.

There are 2 basic forms of mimicry:

1. Batesian – the mimic (palatable) resembles the model (unpalatable) and only the mimic benefits.

2. Mullerian – both the mimic and the model are unpalatable and both benefit.

Batesian mimicry is a form of mimicry where a harmless species evolves to imitate the warning signals of a harmful species (i.e. the unpalatable ones to predators. It is named after the English naturalist Henry Walter Bates, after his work in the rainforests of Brazil. A good example is shown by the volucella hover fly and the classic bumblebee. Batesian Mimicry

Müllerian mimicry is when two or more poisonous species have come to mimic each other’s warning signals. It is named after the German naturalist Fritz Müller, who first proposed the concept in 1878. A good example is shown by the Cuckoo bee and the Yellow Jacket.
Müllerian mimicry

Insect and plant relations

Bee Orchid
In biology, coevolution is “the change of a biological object triggered by the change of a related object.” Well that’s what Wikipedia says anyway. Dr. Francis studies one-to-one relationships between insects and plants. It’s a moot point whether it is the plant using the insect or the insect using the plant.

Pitcher plants actually ingest flies as they tend to live in nitrogen poor areas and “eat” flies to replace this nitrogen. A good example in the UK is something you may have seen before, the Bee Orchid – here on the right. It attracts bees to its flower by actually looking like a bee! I suppose it’s designed to attract randy bees.

Conservation

In many countries conservation is seen as secondary to advancement or development. This is why academic weight is now being thrown behind it. Dr. Francis works in Egypt and sends out students regularly, looks like George chose the wrong Ph.D.

Q&A

You asked what Francis’ favourite mimicry and insects were, and here we go. His favourite mimicry is the Flying Duck Orchid (http://en.wikipedia.org/wiki/Caleana_major) and his favourite insect was one that he saw in his first year of his undergraduate, the Jewel Wasp (http://en.wikipedia.org/wiki/Emerald_cockroach_wasp)
Flying Duck Orchid
Jewel Wasp

Francis Gilbert and the team