Journal archives for August 2017

August 05, 2017

Observation of the Week, 8/4/17



Our Observation of the Week is this Pachyrrynchus congestus beetle, seen in The Philippines by @tonyg

The son of two Biology teachers, Tony Gerard has always been into nature and the outdoors, and he’s even followed in his parents’ footsteps, as a teacher of Biology (and Physical Geography) at Shawnee Community College. “I grew up, and currently live, in an area of great biodiversity- the Cache River wetlands in southern Illinois. It's a great place to visit and an even better place to live!” Tony’s main interest is herpetology (“It's so odd to me that now it's even trendy,” he says, “as a kid I was somewhat ostracized for being the weird kid into snakes and salamanders.”), but he’s also quite interested in other critters such as leeches, flatworms, and gastropods.

And weevils, of course, are also an interest of Tony’s, but mostly in his wife’s homeland, the highlands of Luzon island in the Philippines. “The weevils in the states have always been a nondescript bunch of small brown beetles in my experience,” Tony explains. “Here in the Philippines many are much larger and come in great fun colors and patterns. When they feel threatened they usually just let go and fall into the undergrowth. I've missed a lot of good shots that way. This guy I stuck my hand under as I was focusing - sure enough he dropped - but into my hand. Problem was he didn't want to set still. He kept walking and I had to keep turning my arm to keep up with him.”

There’s not too much information about Pachyrrynchus congestus online, but intrepid iNat user @sambiology was able to dig up this paper, which looks at the structure behind the orange markings of the beetle. From the abstract:

The orange scales that cover the colored rings on the animal’s body were opened, to display the structure responsible for the coloration. This structure is a three-dimensional photonic polycrystal, each grain of which showing a face-centered cubic symmetry. The measured lattice parameter and the observed filling fraction of this structure explain the dominant reflected wavelength in the reddish orange. The long-range disorder introduced by the grain boundaries explains the paradoxical observation that the reflectance, although generated by a photonic crystal, is insensitive to changes in the viewing angle.

“iNaturalist has definitely made me a better naturalist and field biologist,” says Tony (above, with a huge snail in hand). “I'm much more aware and informed about certain groups - especially arthropods and gastropods - from responses I've received on iNaturalist….There is one class I teach, "Field Biology" in which I require students to post observations to iNaturalist. With the current decreases in funding for sciences, iNaturalist is one way in which regular folks can help fill in the gap.”

- by Tony Iwane


 - Like the orange colors on this beetle, many blue colors in nature are structural rather than pigmentary

- There are a ton of awesome organism in the Philippines, check out the faved ones on iNat

Posted on August 05, 2017 05:23 AM by tiwane tiwane | 0 comments | Leave a comment

August 14, 2017

Observation of the Week, 8/14/17


Our Observation of the Week is this Carpathian Blue Slug, seen in the Ukraine by @cloudya!

Originally from Berlin but in America after studying Forest Ecology at Humboldt State University amongst California’s giant Coast Redwoods, Claudia Voigt dug up photos from a survey in Ukraine to show her friends that there’s an “even more magical slug” than North America’s famed Banana slugs.

Three years ago, when she was studying at the University of Sustainable Development in Eberswalde, Germany, “travelled to the Carpathian Biosphere Reserve in Ukraine. The reserve holds one of the only remaining virgin old-growth forests in Europe. We did a rapid biodiversity assessment and studied the impacts to the reserve by the emerging tourism industry but also by changes in traditional land uses. The Carpathian blue slug was one of the amazing endemic creatures of the old-growth beech forest.”

As its common name suggests, the Carpathian blue slug is endemic to the Carpathian Mountain range of Eastern Europe, and is blue in color. The blue ranges from a turquoise to dark blue and even black, and the slug can be found under logs or in the leaf litter in damp conditions. It’s also a large species, with adults growing up to 14 cm in length!

Claudia, who now does forestry work for California State Parks (and is at Jedediah Smith Redwoods State Park in the above photo), says “I always thought of myself more as a naturalist than a forest ecologist or botanist.” Of iNaturalist, she says “[I] am glad that iNaturalist shares observations with other databases. I want researchers to better understand the distributions and ranges of the organisms they study and find the quality control by curators is very important to make iNaturalist a truly valuable tool.”

- by Tony Iwane


- Here’s a Carpathian blue slug in (slow) action: https://www.youtube.com/watch?v=WhgDkkVDwaY

Posted on August 14, 2017 09:25 PM by tiwane tiwane | 0 comments | Leave a comment

August 18, 2017

iNaturalist, Occurrence Data, and Alligator Lizard Mating

iNaturalist is a tool for engagement, helping people around the world get in touch with the life around them and with others who are into nature. But the observations that iNaturalist users collect (over 5.6 million verifiable observations and counting) is also data that can be used by researchers. How does occurrence data from iNaturalist compare to other methods of data collection?

Dr. Greg Pauly (@gregpauly on iNaturalist), Assistant Curator of Herpetology with the Natural History Museum of Los Angeles County and creator of the Reptiles and Amphibians of Southern California (RASCals) project on iNaturalist, recently co-authored Citizen Science as a Tool for Augmenting Museum Collection Data from Urban Areas, which looks at this question. 

Pauly and his co-authors Dakota M. Spear and Kristine Kaiser compared records of four different reptile and amphibian species from VertNet, a database of museum collections, with observations from the RASCals project. They found that in all four species, 

the RASCals citizen-science project generated modern locality records 4–252 times more rapidly than museum collections (Table 1). In 27 months, the RASCals citizen-science project generated 0.36–23.8 times more modern locality records than museum collections acquired over more than 24 years (Table 1). Thus, for three of our four focal species, citizen science provided more data about modern species distributions than the more than 250 natural history collections searchable through the VertNet database.

These numbers are pretty impressive, and as the authors note, up-to-date records are beneficial for giving us a real-time look at species occurrence. It was especially valuable in urban locations, where researchers can’t do exhaustive surveys amongst the “mosaic of private properties that, depending on the taxon of interest, can be difficult or even impossible to survey using standard techniques.”

iNaturalist photos can’t replace museum specimens, which are still hugely important, but “citizen-science projects like RASCals may become a key tool that complements traditional specimen collecting efforts for obtaining data on species distributions throughout the world.”

I had the privilege of speaking with Dr. Pauly in Los Angeles this past May, and here’s a short video of our discussion. He talks about iNat’s importance in understanding urban biodiversity; not only its utility in collection occurrence data, but of rarely observed behaviors such as Alligator lizard mating (see photo above). He and his colleagues at NHMLA are really doing cool stuff with iNaturalist, and I’ll post more videos of them in the future. Check it out! 

- Tony Iwane

Photo credit: Joshua Flatt, CC-BY-NC; https://www.inaturalist.org/observations/7000881

Posted on August 18, 2017 12:35 AM by tiwane tiwane | 0 comments | Leave a comment

August 19, 2017

Observation of the Week, 8/18/80

This amazing conglomeration of Papilio anchisiades idaeus caterpillars, seen in Mexico by luisguillermog, is our Observation of the Day!

A biologist and amateur wildlife photographer who lives in Cancún, on Mexico’s Yucatan peninsula, Luis Guillermo has been working in the jungle for over decades but has never seen an aggregation of caterpillars like the one above, which he photographed.

“The picture was taken in Dzitnup, a tourist site near to Valladolid, Yucatán, during a [family] trip, [this] July,” recalls Luis. “[This was] outside the “cenotes” X’kekén and Samulá…

I was looking for birds when I saw a stain on a tree, but [what] caught my attention [was] the geometric form and then a slight movement. When I saw through the lens could hardly believe that it was a group of caterpillars. I had to look twice. I had never seen this before and I have worked in jungles for 25 years.

Luis said locals “indicated that they had seen before this type of grouping, but they [did] not give me the common name of the "worms" or were they able to tell me that they were butterfly caterpillars. I knew it after, through iNaturalist Page.”

What Luis saw were the caterpillars of the Ruby-spotted swallowtail butterfly. Females of this species lay eggs close together on the leaves of trees in the Rutaceae, or Citrus family, and according Young, et al (1986), “a major feature of larval behavior in P. anchisiades in both field and laboratory is the close physical contact among individuals.” For the first three instars, the caterpillars hang out on leaves during the day and eat at night. They then relocate to the trunks of the tree for instars four and five.

We suggest that aggregative behavior in the larval stages of P. anchisiades enhances visual crypsis to some predators such as birds and lizards. The combined aggregate of several fifth instars on the bark of the host tree creates the image of a mottled blotch of false lichens and bark on the trunk. Similarly, the tightly packed clusters of younger larvae on the ventral surfaces of Citrus leaves resemble dead or dying plant tissue destroyed by a pathogenic microorganism. (Young, et al; 1986)

Like other swallowtail caterpillars, these evert osmeteria when threatened, and “A strong, disagreeable odor, best described as ‘sweaty socks,’ was apparent when the osmeteria of the last two instars were everted.”

Luis, who has over 1,300 observations on iNaturalist, says he uses the iNat “as a form to show the diversity of the Yucatan Peninsula, because I believe that you can only protect or conserve what is known and with the hope to inspire another to observe the richness of life forms around us.”

- by Tony Iwane


- Check out these videos of Ruby-spotted swallowtail caterpillars molting and then metamorphosing!

- Check out the nearly 500 faved observations from the Yucatan Peninsula!

Posted on August 19, 2017 01:04 AM by tiwane tiwane | 0 comments | Leave a comment

August 27, 2017

Observation of the Week, 8/26/80



Our Observation of the Week is this beautiful mother Auplopus wasp, seen in the Sai Kung District of Hong Kong by @wklegend!

“I love nature dated back to my childhood but it was limited only on reading books and watching videos,” recalls Keith Chen (wklegend). “In Hong Kong, the only way to experience nature is to go to the rural areas. Three years ago, I decided to experience the nature with my camera. I took photos of all kinds of creatures. Now I focus on observations of insects and the habit seems [to have turned] into an addiction.”

Keith was on a trip to the Sai Kung district of Hong Kong, and says “I noticed a small wasp handling its prey not far from me. It belongs to one kind of spider wasp that I have never seen before. I approached it carefully and took some photos. The wasp was using its jaws to pick its prey of a spider without legs...I think my movement alerted the wasp, it picked the prey and quickly flew into the bushes. I did not want to disturb it anymore and left the place.”

Like many wasps, the Auplopus wasp that Keith observed is parasitic for part of its life. It belongs to the Pompilidae family, known as “Spider wasps” because of their predilection for spiders as larval hosts. A pompilid female will paralyze a spider with her stinger than drag it to a nest. She’ll then lay an egg on the paralyzed spider and seal up the nest (sometimes with dead ants to deter predators!); once the egg hatches, the larva will eat the still-living spider saving the essential organs for last. This keeps the host alive and fresh for as long as possible. The larva will then pupate and emerge the next year. As an adult, most pompilids feed on nectar or honeydew for energy. Some pompilids, like those in the Auplopus genus that Keith captured, use their powerful mandibles to snip off the host spider’s legs - all the better for transporting to the nest!

Keith (pictured above) at first know which type of wasp he had observed, but @barthelemy, another iNaturalist user, steered him in the right direction. “Thanks to Mr. Barthelemy as he suggested that it was an Auplopus wasp,” says Keith.

- by Tony Iwane


- Pompilid spiders are known to take down prey larger than they are; here’s a mother dragging a nice-sized spider away.

- Check out this Auplopus and her crazy nest from Namibia!

- Nice blog post on pompilids.

Posted on August 27, 2017 04:34 AM by tiwane tiwane | 0 comments | Leave a comment