Facts About Fireflies

  • Fireflies talk to each other with light.

Fireflies emit light mostly to attract mates, although they also communicate for other reasons as well, such as to defend territory and warn predators away. In some firefly species, only one sex lights up. In most, however, both sexes glow; often the male will fly, while females will wait in trees, shrubs and grasses to spot an attractive male. If she finds one, she’ll signal it with a flash of her own.

  • Fireflies produce “cold light.”

Firefly lights are the most efficient lights in the world—100% of the energy is emitted as light. Compare that to an incandescent bulb, which emits 10% of its energy as light and the rest as heat, or a fluorescent bulb, which emits 90% of its energy as light. Because it produces no heat, scientists refer to firefly lights as “cold lights.”

In a firefly’s tail, you’ll find two chemicals: luciferase and luciferin. Luciferin is heat resistant, and it glows under the right conditions. Luciferase is an enzyme that triggers light emission. ATP, a chemical within the firefly’s body, converts to energy and initiates the glow. All living things, not just fireflies, contain ATP.

  • Firefly eggs glow.

Adult fireflies aren’t the only ones that glow. In some species, the larvae and even the eggs emit light. Firefly eggs have been observed to flash in response to stimulus such as gentle tapping or vibrations.

  • Fun Fact: Light Organs

The glow from fireflies or lightning bugs comes from photic organs, or organs that produce light.

  • Fun Fact: Making Light

Fireflies combine three special substances in their photic organs to make light. The three substances are:
luciferin (a pigment),
luciferase (an enzymatic catalyst),
and ATP (nucleotide that provides energy to cells).

  • How to Catch Lightning Bugs

Tips on how best to catch lightning bugs or fireflies. | More

  • Creating Firefly Habitats

What kind of habitat do fireflies like? Why do they like standing water? | More



A new project to create a life-like simulation of Caenohabditis elegans (pictured above), a roundworm. OpenWorm isn’t like these other initiatives; it’s a scrappy, open-source project that began with a tweet and that’s coordinated on Google Hangouts by scientists spread from San Diego to Russia. If it succeeds, it will have created a first in executable biology: a simulated animal using the principles of life to exist on a computer.

Images 1 and 2: Living pluteus larva of the sea biscuit Clypeaster subdepressus under polarized light microscopy. Only the skeleton remains visible. Photos by Bruno C. Vellutini (Wikimedia; Flickr); cc-by-sa

Image 3: Pluteus larva via ccNeLaS

Image 4: Developing pluteus larva. Via Wikimedia. Public domain

Image 5: Sea urchin development tattoo via The Loom

Caption: “Greetings! Here’s a pic of my science tat. I studied sea urchin development for my dissertation. Upon completion 2 yrs ago, I awarded myself this tat for my academic achievement. The tat is of a sea urchin egg, 2 cell embryo, blastula, gastrula, prism stage and pluteus larval stage. Or as my friend’s say, an orange developing into an Alien face-grabber.”

Actinotroch of Phoronis vancouverensis

From Invertebrate Embryology blog

Caption: “These pictures are stacks of confocal images of two different actinotroch larvae of the horseshoe worm Phoronis vancouverensis (Phylum Phoronida). P. vancouverensis is a rather inconspicuous phoronid which lives in small (a few centimeters long) muddy tubes in clumps, attached to some sort of hard substratum (a rock, a floating dock) often in somewhat muddy surroundings. This species broods its larvae in the crown of tentacles, called the lophophore. I gently shook the larvae out of the lophophore of an adult and prepared them for confocal microscopy with my students while teaching the Comparative Embryology course at the Friday Harbor Labs in the Summer 2007.

We preserved the larvae and stained them with fluorescent phallodin (a toxin, derived from the deathcap mushroom Amanita phalloides), which binds to filamentous actin. Muscles are highlighted because they are full of actin, a protein which enables cellular contractility. So, most of what you see on these pictures are muscle fibers. There is also quite a bit of actin in the cell cortex (the region of the cytoplasm adjacent to the plasma membrane). So, the outlines of epidermal cells are often also labeled with phalloidin.”


For such tiny animals, Syllidae really get around.

These polychaete worms, most only a few millimeters long, are found from the intertidal to the deep sea. The over 200 species of Syllids, and potentially many more not yet recognized, are keeping some molecular biologists very busy. 133 species from 5 continents have DNA barcodes already, and our colleagues at the Moorea Biocode project just keep finding more, just waiting to be identified, or classified as new species.

More Syllids from Moorea here.

(via: Encyclopedia of Life)

This is a Bryozoan statoblast. It is a cyst that can survive over the winter and begin a new Bryozoan colony when conditions permit. The little anchor shaped hooks really cling to things and allow the statoblast to hitch a ride on vegatation or animals. ” Photos by Charles Krebs

Image 1: A dish of millipedes under UV light. Most of the ones fluorescing in blue are Semionellus placidus, while the two fluorescing red are Pseudopolydesmus serratus. Red fluorescence under UV hasn’t been reported before in arthropods, to my knowledge.”

Photos by Derek Hennen. Check out his blog post for more field notes and details on identification!

Image 2: Semionellus placidus, photo by Derek Hennen (source)


Terrifying (but tiny!) bryozoans

Images 1 and 2: Beania mirabilis (source) cc-by-nc-sa

Image 3: Electra monostachys (source) cc-by-nc-sa

Image 1: “Scanning electron microscope image of a bryozoan colony” (Source)

Image 2: “This skeleton of a living bryozoan, collected at Bahia de los Angeles, Baja California, clearly shows this typical colonial organiation.

Each individual, or zooid, is enclosed in a sheath of tissue, the zooecium, that in many species secretes a rigid skeleton of calcium carbonate. Each zooid in this electron micrograph is less than a millimeter long and has a single opening, the orifice. Through this opening, the lophophore, a ring of ciliated tentacles centered on the mouth, protrudes to capture small food particles. The lophophore can be retracted very rapidly by specialized retractor muscles, and the opening closed by a doorlike operculum, visible on some of the zooids in the picture at the left.”


Image 3: Membraniporella nitida (source) cc-by-nc-sa

More info:

Pygites brachiopods… or bizarre fossil scrotal phylogeny?

Images 1 and 2: Source. In German. 

Image 3: Source

Caption: “Pygites is unusual for a Terebratulid brachiopod. It shares many of the same features that other brachiopods in it’s order except that it has a hole in the middle of it. The hole is created as the shell grows and splits into lobes that then eventually meet back together and enclose a hollow area. This is odd behavior for a brachiopodand I’ve only seen a handful of genera that have even exaggerated lobes, such as Dicoelosia from the Haragan formation, let alone those that surround a hole. Below are three specimens from the Cretaceous (Hauterivian stage) of Spain that show you the variation in the genera.”

Image 4: ”Pygites diphyoides (d’Orbigny, 1849) from the Hauterivian (Lower Cretaceous) of Cehegin, Murcia, Spain. This terebratulid is characterized by a central perforation through its valves.” Source: Wikipedia; cc-by-sa

Image 5: Pygites diphyoides (source)

More brachiopods! The spiral lophophores are a filtering apparatus. 

Image 1: “Fig. 8. Hypothetical representation of efficiency of the filtering system of some extinct spire-bearing brachiopods showing flow patterns and extension of area for trapping food resources. Inhalant and exhalant currents according toVogel (1975) and diagram modified from Ager and Riggs (1964).”

Image 2: “Fig. 9. Hypothetical representation of efficiency of the filtering system present in extinct productid brachiopods showing flow patterns and extension of area for trapping food resources. Inhalant and exhalant currents as in a similar model proposed for Falafer Grant (1972) and diagram modified from Brunton et al. (2000) without including his interpretations.”


Pérez-Huerta and Sheldon. 2006. “Pennsylvanian sea level cycles, nutrient availability and brachiopod paleoecology.” Palaeogeography, Palaeoclimatology, Palaeoecology. Volume 230, Issues 3–4, 30 January 2006, Pages 264–279.