Foreword
This is not a usual blog. This essay was inspired by work I did producing the program I put on at the Keiki Museum. As you will see, the information was better directed to adults rather than keikis. Seven years ago Sandra and I were butterfly novices, inspired ot make paper mache buttrflies. In the process, we became more interested in the animals themselves. With help from some patient teachers, and I would single out Daniel Rubinoff, Jeffrey Pippen and Caitlin LaBar, we have received an education in lepidoptery. Here we attempt to pass on what we have learned at the knee of these masters.
The Butterflies of Hawaii Island
Hawaii is one of the most isolated places on earth. By the time the Polynesians set foot in Hawaii (roughly 1500 ears ago), Homo Sapiens had been traipsing around North America for over 30,000 years and Europeans didn't "discover" Hawaii until roughly 250 years ago.
The geographical isolation had a significant impact on the plants and animals that the Polynesians encountered. Science believes that plants came to Hawaii 80 million years ago. Insects like butterflies began inhabiting the island chain 12 million years ago. Compared to our brief stay on these islands, that is a staggering amount of time.
Some animals and plants leave a better fossil record that others. The fossil record tells us that in the mass extinction that followed the arrival of Homo sapiens in Hawaii, around 50 species of birds became extinct. Its not clear how many butterflies and plants might have been lost as they leave a less definite footprint. Much of the extinction of birds was due to a large number of flightless species, ducks and the like, that had little defense against the rats that accompanied the Polynesians. Wherever human beings have gone, they bring rats. Its just what we do.
The bottom line: we now have two endemic butterflies and we have no way of knowing how many species might have existed when Kamehameha's forebears arrived in Hawaii.
A brief look at butterfly taxonomy and anatomy.
Butterflies are arthropods, insects, centipedes, spiders and crustaceans comprise the phylum Arthropoda. They all have a stiff outer exoskeleton and jointed limbs.
Crustaceans have gills, presumably because its more difficult to extract oxygen from water than air. The terrestrial arthropods have neither heart nor lungs. So while your thorax houses those vital organs, the insect thorax is little more than a platform for legs and wings
Butterflies have little in the way of a vascular system. A vessel in the abdomen collects haemolymph, which has been flowing free inside the body cavity and muscles surrounding this vessel, sort of like a heart, massage it cranially. As an interesting aside, when a lepidopterist (read butterfly killer) like my dear friend and teacher, Caitlin LaBar, nets a butterfly, she squeezes the abdomen just so, stopping what passes for a heart.
Oxygenation takes place through tiny vents in the exoskeleton called trachea. Amazingly, in the lymph there are no red blood cells or proteins like hemoglobin that bind and then release oxygen. The oxygen insects use is simply dissolved in the blood. In mammals, about 2% of the oxygen is dissolved in the blood, the other 98% carried in the hemoglobin. Insects are getting by on what us mammals might consider an after thought! And its astonishing, given that over the 60 million years that insects have been prevalent, they haven't evolved a protein that carries the good old green gas, oxygen. One has to assume that for them its irrelevant.
If you don't think that insects are prevelant, consider that there are more species of insects than there are for all other groups of animals combined. Prevalent.
Many butterflies have six legs, but about half bear only four, the anterior pair having evolved into manipulators. this large group is called brushfoots. Good name for a family of hobbits, right?
And, of course, butterflies have two pairs of beautiful wings. If it weren't for the beautiful wings, most of us wouldn't give a fig for butterflies. Each wing has a dorsal and ventral surface. In some butterflies, the two are virtually identical. Monarchs are like that. In many, there is a dramatic difference in the two surfaces, the ventral often being drab or bearing spots.
What gives these butterflies their beautiful color and pattern. Its scales, millions of them. In the finest Persian carpet, woven with silk, there are 500 knots to the square inch. In a butterfly wing thee are 200 to 450 scales per square millimeter. a few months ago I thought i would take a used butterfly wing to a lecture and have have the attendees look at the scales through a magnifying glass. Upon learning this, I decided that I would need to bring along my electron microscope in addition to the butterfly wing.
Aside from flight, butterflies have a couple other uses for their wings. In the morning they will spread their wings and orient towards the sun; the wings serve as solar collectors, warming the butterfly. When resting, butterflies bring their wings to an upright position above the body. They can rotate the back wings, often more cryptically colored, to cover the front wings, rendering the butterfly some camouflage.
Butterfly heads are full of amazements. First the eyes. Insects have compound eyes comprised of hundreds of individual optical cells. These connect with nervous ganglia. butterflies don't have brains, but they can see. Heaven only knows just what they see, but they do.
Butterflies do not have mouths. If you think about it, this is sort of unusual in the animal kingdom.
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| Look carefully to see the long, curved proboscis |
Its hard to imagine what sort of evolutionary pressure caused them to substitute a thin tube, called a proboscis, for a mouth. The proboscis is about as thick as a piece of fishing line, making one wonder how they are able to suck nectar (and other stuff, some quite viscous) through such an incredibly narrow tube. There are tiny muscles in the cheeks that assist in sucking.
And what about those antennae. I'm reminded of Jon Belushi and his SNL Bees and that sitcom Martian from long ago. Being actually human, they had all the sensory organs we know and love, so in their case just what the antennae did is up for grabs. In fact, butterfly antennae are sensitive chemo receptors. They are extremely sensitive and specific to the needs of a butterfly. They detect pheromones, especially for males locating females over long distances. They detect nectar and other things that the butterfly wants to ingest, some rather disgusting. And, especially in females, host plants. We will discuss the relationship between butterflies and host plant below.
The Butterfly Life Cycle
The butterfly lifecycle in some respects is similar to other animals, mostly it is wildly different. So what came first, the chicken or the egg. The fertilized egg, a combination of male and female products of conception along with a nutritious yolk is found throughout the animal kingdom. If you think of the diverse animals that have adopted the egg as part of their lifecycle, independently through evolution, its overwhelming.
In the case of Hawaii, we can say that a fertilized butterfly probably landed here and deposited her eggs. At least twice. .Eggs for each species are very small, about one mm., and they are all a bit different.
Female butterflies lay several hundred eggs individually, usually on the underside of the leaf of their host plant. The host plant is one that the female knows her caterpillars will be able to eat. When that first butterfly landed in Hawaii, it had to find a host plant. Over millions of generations our endemic butterflies have developed host plant relationships with very specific plants now found mostly in highland forests. The egg hatches in about six days.
As an aside, for each species of butterfly there is a parasitic wasp that lays eggs inside the butterfly egg. And there are other wasps that lay eggs inside caterpillars. The insect world doesn't miss a trick.
Emerging from the tiny egg is a tiny caterpillar, a first only a mm or two long. The caterpillar eats voraciously for about three weeks. As it grows it molts,usually four or five times, depending on the species. The different caterpillar forms between molts are called instars. Frequently the progressive instars look significantly different from one another.
The penultimate instar goes through a final molt and becomes the chrysalis. In Hawaii, two different strategies are employed. The Monarch, Kamehameha and Gulf Frit lay down a single patch of silk and hook into this with their cremaster, a small hook at the tail end, hang upside down and go chrysalis. The Asian Swallowtail and Large Orange Sulfur lay down two patches of silk on each side of a branch and a third below, They then attach the sides of the chrysalis with silk threads to the upper two patches. The tail end of the caterpillar is attached, via the cremaster, to the third, dependent silk patch.
The silk is produced in the mouth in a modified salivary gland and a spinerette. It is both extremely strong and sticky.
While the caterpillar was eating and growing, he was also producing imaginal discs. These structures contain the information necessary to reconstruct the butterfly. Because, once the caterpillar goes chrysalis, it releases chemicals that liquefy the organism within. So early on the chrysalis is full of caterpillar soup with the appropriate number of imaginal discs. The imaginal discs get going and the various parts of the butterfly come into being It takes about two weeks for the liquefied caterpillar to be reconstructed into a fully developed butterfly.
If you don't believe in God (and I guess I respect that) you might consider this metamorphosis and ask yourself, "Is there any ther reasonable explanation outside a divine presence?"
The butterfly emerges from the chrysalis. Like one of those chairs you purchase at Costco, with the shock cords that connect the various legs and so forth, the butterfly ends up much larger than the tiny package it came in. A monarch chrysalis is basically a tube about one inch in length and 4mm in diameter. Once the emerged monarch has pumped his wings, moving fluid around the body, he is almost two inches long and has a wing span of three inches or more. Go figure.
Although butterflies give us pleasure, they were born, if you will, to reproduce. And they only have three weeks or so to get this done. They are a bug on a mission. Males will nectar, but they will also go to muddy places or find other sources of vitamins and minerals, which they suck up iwth their proboscis. One trick in finding butterflies is to go to riverbanks and look for males with their beaks in the sand sucking up nutrients. butterfly watchers call this a puddle party. If you are lucky, you may see several different species at one such get together.
Having done their best to accumulate what the female needs, they find a female, who is helping them along by emitting pheremones and the engage in S E X. In addition to sperm, the male passes along these nutrients, which lepidopoterists call conjugal gifts.
The female lays her 200 eggs and the process repeats.
Garden Butterflies
The introduced butterflies on Hawaii Island, from the stand point of life cycle, might all be called Garden Butterflies. They go about their business with little regard for seasonality. In one sense, this is surprising because there is clear indication of seasonality in our introduced flowering trees, our introduced birds and our reef fish. Nevertheless, you can find monarch caterpillars in every month of the year.
This is hardly the case in butterflies that occupy temperate North America. Here are three strategies those butterflies employ. Monarchs migrate. Those to the east of the Rockies migrate to pine forests in Central Mexico. Those to the west migrate to coastal California. There is a gentleman in San Francisco who is exciting the ire of the Monarch community by turning his property into a garden butterfly monarch community, where the species looses its seasonal approach, much as it does here in Hawaii. It is likely that the migrating monarchs remain in sexual diapause through the winter, breeding again in March before migrating north.
Mourning Cloak Butterflies, at the end of the fall season, crawl into a protected spot, like a rotting stump, and overwinter. this same adult emerges in late spring to start breeding.
Many butterflies overwinter as pupa, in chrysalis form.
One might think that when spring arrives, butterflies just jump tight in and start cycling as they do in Hawaii. This is far from the case. somehow each species synchronizes within itself. Between mid-May and September a species might go through 2 or 3 cycles, leaving many weeks when the adults are not seen. Astute lepidopterists can alert us to the presence of adult butterflies, which one might otherwise easily miss.
Dr Rubinoff tells us that the two native butterflies on Hawaii island, while present throughout the year, do exhibit some seasonality. In fact, the Koa butterfly may be exhibiting an uptick in breeding in January, associated with the growing season of its host plants.
So head mauka, look under leaves and with luck you will find a Kamehameha or Koa Butterfly caterpillar!
jeff
A brief history of Biologists in Hawaii with an emphasis on butterflies
The first biologic record by Europeans came on Cook's third voyage.
Realizing the importance of a natural historian, Cook recruited two.
When he arrived on Hawaii Island, the senior botanist was ill and unable
to go ashore. The junior botanist was David Nelson. Nelson had been
discovered as a gardener at Kew,Gardens and received some formal training before
the voyage, possibly from Joseph Banks. Nelson attempted to climb Mauna Loa, and collected 136
species of plants and a number of birds. which are now in the British
Museum. He went on to be the botanist on the HMS Bounty, responsible
for the breadfruit in the main cabin. Loyal to Captain Bligh, he made
the 3800 mile voyage in the open boat, only to die of a fever on Tmor.
There is no record of Nelson finding butterflies in Hawaii. One should view this as the first testimony as to how difficult it was (and is) to find the Kamehameha Butterfly Even at the time of first European contact, preceding the deforestation caused by the sandalwood trade, a talented naturalist did not record one butterfly
Johann Friedrich Gustav von Eschscholtz, in contrast to David Nelson, was an aristocrat. Residing in a university town in what is now Estonia, he studied medicine, zoology and botany. He became the ship surgeon and one of two science officers for the voyage of the Rurik, a voyage of exploration sponsored by Nikolai Rumyantsev, First Secretary to Alexander I.
Like Cook, Otto von Kotzebue who commanded the sailing brig Rurik, was charged with finding the Northwest Passage. While Cook was exploring the Pacific, George III was fighting the American Revolution. While von Kotzebue was exploring the Pacific, Alexander I was fighting Napoleon. Curiously, Tolstoy did not write a monumental novel about Pacific exploration.
The Rurik circumnavigated, stopping in Hawaii twice. Eschscholtz is credited with discovering and naming the Kamehameha Butterfly, his description being accepted in 1821. Von Kotzebue and Eschscholtz teamed up for a second voyage In 1823 Von Kotzebue was given command of two ships of war, charged with resupplying kamchatka and protecting Russian interests in Alaska. On this voyage they once again stopped in Hawaii. .
No lightweight, as a result his two voyages of exploration, he Eschscholtz is credited with discovering an naming a slew of plants and animals from beetles, nudibrnchs and jellyfish to a flying fox and a couple monkeys.
Its sad, but despite a determined search, I can find no information on the person credited with discovering Blackbun's Blue Butterfly. We are left with Tuely 1878. We'll keep on it and provide an update when we can.
It is a well established fact that Hollywood rewrites history. For example, my impressions of world War II are greatly influenced by George C Scott in Patton and Tom Hanks, et al. in Saving Private Ryan. With that in mind, I would like to recommend two movies. The first is Master and Commander, starring Russell Crowe as Lucky Jack Aubrey and Paul Bettany as Stephen Maturin. The story takes place at exactly the same time that von Kotzebue and Eschscholtz were sailing on the Rurik. And the similarities between Stephen Maturin, physician and naturalist, and Eschscholtz are remarkable. Its hard to believe that Patrick O'Brien was unaware of this. At any rate, watch master and commander and get a feel for what it was like sailing at the time the our pulelehua was discovered.
the second film i would recommend is Mutiny on the Bounty. Actually you have your choice of 5 films. Whether you like Marlon Brando or Anthony Hopkins, you will still see david Nelson caring for his breadfruit and being put into the open boat iwth Captain Bligh.
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