Bugs are Amazing!

Well, it’s officially summer here in Texas and Houston is literally buzzing with insect activity! I don’t know about you, but I have about 18 mosquito bites and I’m sure there will be many more to come. Bugs are everywhere now and this is the best time of year for them.

People always ask me why I’m so interested in bugs and why would I want to work with them for a living. Most people are so concerned with how gross or weird they are to see how amazing they can be. The more I get to know them, the more I want to know – they just blow me away! Hopefully you will feel the same. I wanted to share some amazing insect facts with ya’ll so maybe while you’re out and about this summer, you’ll think a little differently about our little friends!

First thing’s first, Arthropods are the phylum that insects belong to and includes all of their close relatives like arachnids, crustaceans, and myriapods. There are an estimated 1,170,000 known species on earth. Those are only the ones we know about; there are probably millions more waiting to be discovered!

Of these, about 1,000,000 species are insects, which account for more than half of all known living species on earth…that’s amazing! Scientists believe that there are up to 9,000,000 more species that have yet to be discovered, OMG.

So lets compare that with some other animals shall we? There are 5400 species of mammals, 10,000 species of birds, 8200 species of reptiles, and somewhere around 6000 species of amphibians.

3 - Hi YA YA!
Creative Commons License photo credit: robstephaustralia

The largest order of insects are the beetles with 350,000 species making them the most abundant animal on earth. In fact, 1 in every 4 animals is a beetle! Coming in second are butterflies and moths, with 170,000 species. The largest insect (heaviest) is a beetle called the Goliath Beetle. They can weigh 4 ounces, which is as much as a quarter pound burger (meat only.) The longest is a walking stick from Southeast Asia measuring 22 inches.

Think insects all have short lifespans? Think again. Cicadas can live 17 years underground before becoming adults, ant and bee queens can live for decades and one type of wood boring beetle emerged as an adult after being in a bookcase for 40 years, yikes!

The loudest insect is an African cicada. We are used to hearing cicadas during the hot summer days. I heard cicadas in Costa Rica that were so loud I thought they were birds at first! The African cicada can produce sounds that have been recorded at 106.7 decibels. In comparison, a jackhammer produces about 100 decibels.

grasshopper chomping on my leg hair
Creative Commons License photo credit: slopjop

Most people know that Monarch butterflies migrate pretty far, but did you know that locusts travel much further? They have them beat by a couple thousand miles. They have been known to travel nearly 3000 miles one way! One species even flew from Africa, across the Atlantic ocean to South America; now that’s amazing! They also win in terms of the largest swarms. The largest swarm was recorded in Africa in 1954. It was so huge it covered an area of 77 square miles. That’s kind of scary.

Insects are pretty amazing fliers. They were the first animals to take to the air, about 200 million years before the first birds. Dragonflies are up there, having been clocked at 36 miles per hour, but the horsefly can reach speeds of more than 90 miles per hour! A hummingbird can beat its wings about 60-80 times per second,  pretty impressive. A tiny fly called a midge can beat its wings up to 1000 times per SECOND, that’s unbelievable.

When it comes to foot racing, we do have a super star, right here in Houston. The American cockroach(big one with wings) can reach speeds of 3.4 miles per hour. Now that doesn’t sound fast, but in human terms, it would be like one of us running 400 miles per hour. The Australian tiger beetle is the fastest clocking in at 5.6 mph, which is the equivalent of 720 mph for a human.

European rhino beetle taking a walk on a concrete mixer
Creative Commons License photo credit: e³°°°

All insects are of course very strong, being able to carry or move things many many times their own body weight. A well known beetle, the rhino beetle can carry up to 850 times its own weight. That would be like an average guy, maybe 175 pounds, being able to lift 150,000 pounds. Good luck with that!

So see, insects are pretty darn incredible. It may even make you feel better to know that out of the million species of insects that exist on earth, less than 1 percent are considered to be pests or harmful to humans. The vast majority live in tropical regions like Asia, Africa, and South America, with the highest concentration in rainforests. I could go on and on about the feats of insects, but I’ll save some  for another time. Until then, I hope you all can learn to appreciate the most incredible, beautiful, and diverse life forms on our planet. Happy bug watching!

Searching for Elvis, (Jim, Janice and Jimi)…

So far many of the tales I have told (all true by the way) have dealt with a common underlying theme – life through the eyes of a budding young scientist.  This is because I have hacked away at information from old camp logs and field notes from the early days in my career to bring you, the reader, vivid pictures through these stories.  The next reading is no different except that it takes place not in Latin America, but here in our own backyard, the USA; specifically, southeast Arizona. 

Approximately 15 years ago, while working in a job that involved little variation in day-to-day work, one of my co-workers, Jerry CrabbyOtis (Crabby hereafter) and I would take up the topic of bird-watching (birding), which we both enjoyed thoroughly.  He was much better at birding than I, as he had been doing it for a longer period of time than I. 

One day Crabby returned from a trip to the Chiricahua Mountains of southeast Arizona.  Before leaving for Arizona, Crabby was stressed out, malnourished, and probably had a G-I tract perforated with ulcers.  When he returned only a week or two later, it was like he had been sent to a rapid-advance rehab facility – he was relaxed, bronze-colored from the sun, and full of more excitement than you could shake a stick at!  It was as if he was a Greek leprechaun who had found a pot of gold, returning to report his quarry. 

“DAN – you gotta go to the Chiricahuas man…,” he said, trying to get my attention.  After he described the beautiful northern offshoot of Mexico’s Sierra Madre, and all of the tropical wildlife that thrived there, I decided a trip could well be in order. 

I telephoned a friend, Steve Mayes, who was also doing the daily grind and in need of a fun diversionary field trip.  Steve and I planned our trip to take place later that summer.  We charted all the hot spots for tropical wildlife (especially birds) in southeast Arizona.  This would be a great opportunity to do a little field work and collect scientific data on various topics involving animal foraging.  I had just received my Master’s degree and wanted to take a stab at designing my own experiment, independent of an experienced mentor.

Above all, we joked around about the possibility of finding Elvis Presley, Jim Morrison, Janice Joplin or Jimi Hendrix on a street in Tucson.  These talented musicians, who all met a tragic end, were the subject of urban myths, perpetuating they had moved to Tucson after becoming weary of the daily grind of a famous musician.  We knew the trip would be fun, and after all, someone once said, “Nothing is worth doing unless you are having fun.” 

As evening falls
Creative Commons License photo credit: kretyen

Searching for Elvis, (Jim, Janice and Jimi)…

August 1994
Tucson, Arizona

When we arrived in the late afternoon, worn out and exhausted from the long and grueling drive from Texas, we scouted a bit and pitched camp in this ‘foreign,’ yet beautiful, habitat.  I cautiously prepared the feeding tubes with three different concentrations of sugar water: no sugar in the control, 5% sugar and 20% sugar.  Then proceeded to hang the feeders at the same height and distance from one-another.  I was a little nervous, as this was my first ‘solo flight’ with experimental design. 

Within a few minutes of dusk approaching, several nectar-feeding Long-nosed Bats (Leptonycteris curasoae) began hitting the feeders.  Within a few minutes of that, the bats figured out which feeder was most concentrated with sugar and ignored the other two.  Risk-sensitive foraging in action!  The same pattern was observed the following morning with the hummingbirds, and within a few minutes of that the hummingbirds illustrated extreme size-mediated competition, with the larger species ousting the smaller species from the feeders.  This pattern held for each site we ran the experiment at, all at varying altitudes with a different of hummingbird community.  My experiment worked!! 

Elegant Trogon
Creative Commons License photo credit: dominic sherony

That first morning at Sunny Flats, we set out to see what wildlife we could see in this semi-mesic Oak forest surrounded by low-lying desert.  One of the first birds we saw was one of the primary target species – a female Elegant Trogon (Trogon elegans) feeding her youngster.  Shortly thereafter we saw a mixed flock comprised of three Bridled Titmice (Parus wollweberi), two Yellow Warblers (Dendroica petechia) and a Painted Redstart (Myioborus pictus), with the latter being the alarm-calling sentinel, warning the other birds of our presence.  We even saw a lone male Coati (Nasua narica) on the way back to camp, rooting around in the understory. 

Things like the trogons, coatis, and other Neotropical species we saw are difficult to impossible to view in other regions of the the U.S., so being able to see these tropical species in this region was a genuine thrill!

One of several other sites we visited was a Nature Conservancy property called Ramsey Canyon.  Within a few minutes of leaving the truck, we saw a sow and half grown cub cinnamon-phased Black Bear (Ursus americanus) strolling leisurely at the bottom of a hill, perhaps 100 yards or less from where we stood.  I could feel the hair on the back of my neck stand.  It was Ramsey Canyon where we hoped to see the Eared Quetzal (or Trogon, Euptilotis neoxenus).  After spending several hours hiking up mountainsides into appropriate habitat where we might encounter the bird, we struck out and finally threw in the towel a little before dusk.  We were juiced to continue our long and grueling hike, as we thought (?) we heard vocalizations, which drove us to continue on our quest for this cryptic species.

Black Bears ended up being somewhat common in southeast Arizona.  In fact, we found several piles of fresh bear dung, full of the berries that were in full bloom in the arid mountains of this region.  [At the time, I was very interested in ecological interactions of South American fauna and flora (as I still am today)].  One of the fascinating new findings in South America was that a carnivore, the Maned Wolf (Chrysocyon brachyurus), was actually an important disperser of some of the fruits it preferred to eat.  So naturally, I wanted to see if the Black Bears were dispersers or predators of the berries they consumed.  I had to bring Crabby back some sort of ‘gift’, so I figured, why not some bear feces to do germination experiments with, since he had such green thumbs after all!

Now we’re sitting on a bench in an urban park, catching our breath after playing Frisbee, and getting caught up on the field notes.  We have looked high and low for Band-tailed Pigeons (Patagioenas fasciata) with no luck, despite being the right time of year to catch a glimpse.  Steve was relaxing, contemplating his surroundings, as he often does.  Then he looks over at me calmly, hits my arm to get my attention, and upon doing so just holds his hand with his index finger pointing towards the sky.  Following his directions, I see a resting Band-tailed Pigeon perched just a few feet over our heads.

Post-log (12 January 2009):Well, Crabby’s bear dung never germinated any sprouts of a plant despite his green thumbs, which told us the bears are actually seed predators in this case.  The lesson learned with the Band-tailed Pigeon has again and again provided some of the most obvious answers to some of the most daunting tasks or questions I have encountered in life thus far.  That is, that the answers are often right in front of our faces, if we can just slow down long enough to ‘see’ them.  I have remembered this hilarious moment of the Band-tailed Pigeon perched over our heads, yet have found it to be so true in tackling research questions, dealing with crazy personalities, and other formats of problem solving – the solution is often right in front of you.  Even though we never met up with Elvis, Jim, Janice or Jimi, I could have sworn I caught a fleeting glimpse of one, or the other, out of the corner of my eye on several occasions.

Hummingbirds of the Night

A few nights ago I saw what I thought was a hummingbird – out way past its bedtime – whirring around the fragrant, long-tubed blooms of the Rangoon creeper in my back yard.  As I watched, several more of these curfew-breakers appeared, working the flowers all up and down the fence.  I soon realized that these were not in fact hummingbirds, but were their nocturnal analogs:  hawk moths or sphinx moths.

Pandorus Sphinx Moth
Creative Commons License photo credit: August Norman
 Pandorus sphinx

Talk about convergence!  If they hadn’t been flying at night – and there are some day-flying sphinx moths, by the way – I would have been hard put to tell they weren’t ruby-throated hummers (the most common hummingbird species in our area).  The sphinx moth in question (probably the five-spotted hawkmoth, Manduca quinquemaculata) is about the same size and shape as a ruby-throat, with a bullet-shaped, streamlined body, and has exactly the same behavior.  The powerful wings of both hummers and sphinx moths beat so swiftly (up to 50 or so beats per second) that they are just a blur in flight.  Both can hover up, down, back and forth, helicopter-like.  Instead of a hummingbird’s long bill, sphinx moths have a long tongue or proboscis, kept rolled up when not in use and extended when reaching for nectar at the base of a long-tubed flower. 

Rangoon creeper - flowers are first white, turning red the next morning

Rangoon creeper - flowers are first white, turning red the next morning

Both hummers and sphinx moths are important pollinators, and certain plants have evolved flowers that are specifically “designed” to attract these powerful fliers with their long beaks or tongues.  Such flowers typically have abundant nectar at the base of elongated floral tubes (the bottom part of the petals grows together to form a hollow tube).  But while hummingbird flowers are usually brightly colored (especially red) and often do not have any scent (since hummingbirds can’t smell), moth-pollinated flowers are typically white or pale-colored, and often emit a strong, sweet scent as the sun goes down.   

The family of sphinx moths, the Sphingidae, is a large one, with about 1200 species world-wide (most are tropical).  There are about 60 species of sphinx moths in North America, several of which occur locally.  Some of the most common species in our area are the Five-spotted sphinx, the Carolina sphinx, the Rustic sphinx, the Pink-spotted hawkmoth, White-lined sphinx, Tersa sphinx, Vine sphinx, and Pandorus sphinx

Another spectacular species, which occasionally ranges up from the tropics into our area, is the Giant sphinx.  This very large moth (over six inches across) is notable as the pollinator of the rare ghost orchid of Florida’s swamps, Dendrophylax lindenii.  Made famous in the book “The Orchid Thief” on which the movie “Adaptation” was based, this orchid has an extremely long, thin floral tube and depends on the giant sphinx moth to transfer pollen from one bloom to another in order to reproduce.  Take a look at the specimen of the giant sphinx from our collection.  Uncoiled, its tongue is almost nine inches long, almost twice as long as its body! 

Giant sphinx moth with proboscis extended

Giant sphinx moth with proboscis extended

This moth is the New World equivalent of the renowned “Darwin’s moth.”  As the story goes, when in Madagascar, Charles Darwin saw the orchid Angraecum sesquipidale (rather similar to the ghost orchid).  He postulated that there must be a moth with a tongue of equal length to the orchid’s 11 inch nectar spur that would serve as its pollinator.  Sure enough, 41 years later (long after Darwin’s death), such a moth was discovered and its common name acknowledges his prescience.

tomato hornworm
Creative Commons License  photo credit: naturegirl 78
Tomato hornworm
(Manduca quinquemaculata)

Sphinx moth caterpillars are called “hornworms” because most of them have a distinctive horn that sticks up at the end of their abdomen.  If you are a gardener you may have encountered large, green hornworms devouring the foliage of your tomato plants; these turn into the five-spotted hawkmoth I saw visiting my Rangoon creeper.  Another hornworm frequently seen in the garden (if you grow pentas or star-flower) is the caterpillar of the Tersa sphinx, Xylophanes tersa.  This caterpillar turns from green to brown as it grows, and has a pair of dramatic eyespots on its thorax.  People sometimes confuse it with the caterpillar of the spicebush swallowtail. While hornworms can eat a lot of foliage, I confess that in my garden they are welcome to it – I like the adult moths too much to consider destroying their destructive “baby” stage…  Besides, I think the caterpillars themselves are rather handsome! 

If you find a hornworm and want to rear it, be sure to provide it with a couple of inches of loose soil when it gets large enough to pupate.  Most sphinx moths pupate in the soil, and do not spin cocoons around the brown pupa.  Some sphinx pupae have the tongue pulled away from the body, resembling the handle on a pitcher or Greek vase!  Don’t disturb the caterpillar/pupa for several days after it burrows down or you may disrupt the pupation process. 

Whether or not you get into the caterpillars, it is always a thrill to see an adult sphinx moth in action.  To attract these nocturnal hummingbirds to your garden, consider planting some of the following.  As an added benefit, you’ll enjoy the wonderful fragrance on evenings when these plants are in flower.

Mirabilis
Creative Commons License  photo credit: sigusr0
Four O’clock (note long tube)

Angel’s trumpet (Brugmansia candida)

Jimsonweed or Datura (Daturaspp.)

Night-blooming jasmine (Cestrum nocturnum)

Rangoon creeper (Quisqualis indica)

Moon flower (Ipomea alba)

Four O’clocks (Mirabilis spp.)

Evening primrose (Oenothera spp.)

Petunias (Petunia spp.)

A Welcome Visitor

giant-swallowtail-butterflies-feeding-on-bauhinia-resize.jpg

I thought I might share with you a glimpse of a beautiful Giant Swallowtail butterfly that visited the White Orchid Tree (Bauhinia mexicana) in my back yard.  I purchased this tree from one of our Fall Plant sales after I saw some hummingbirds feeding from the blooms. 

The plant was sitting just outside the greenhouse basking in the sunshine.  I figured that if the ruby throated hummingbird could find this delectable treat way up on the rooftop of the museum’s parking garage, it would surely find it in my yard. 

I took one home and planted it just outside my back door in full sun.  The beautiful white blooms fill the outer tips of the branches in such a way that it resembles a fine lace in the distance.

giant-swallowtail-larvae-cbc-on-citrusresize.jpg

Giant Swallowtail Caterpillars

This visual appeal was too much for these two Giant Swallowtails to resist as they visited in unison one day while I was home.  I immediately ran to get my camera and take their picture.  To my delight just after they fed on the blooms, they lighted on my Meyer Lemon Tree to lay some eggs.   (The citrus tree is one of their host plants.) 

I wanted to take the larvae to the museum and utilize them as an educational tool for a gardening workshop.  Because I did not have any citrus trees at the museum to use as food for them, I cut some stems from the citrus in my yard and fed the fresh food to the caterpillars every day.

While the caterpillars went through their life cycle, I housed them in a plastic, 2 gallon aquarium with a mesh screen for a lid.  When they were ready to pupate, they attached themselves to the interior of the lid with silk and went through their metamorphosis.  I was able to use them as a teaching tool at the workshop and also release them into the exterior butterfly demonstration garden where they could feed freely and bask in the sun.