Snack time! Here is a case of negative results reported in the literature: eating curcubitacins does not offer protection from birds [though human subjects agree that such beetles only taste bitter after they've eaten cucumber seeds (n=20)]. DOI:10.1111/j.1570-7458.1984.tb03439.x
2022-10-09 Lake Lily, Cape May, NJ
A lone Macrosiphum euphorbiae on our bearded iris. Given her reproduction rate (10 generations at 70 aphids per generation equals a billion squared aphids by the end of summer) it's a good thing she has many predators, parasites and pathogens. She achieves this great fecundity via cloning, giving birth to live young who are born pregnant, shortening the time between generations. Later generations may include winged males and females so sex can work its evolutionary magic.
2022-10-15 Bethesda, MD
Conoclinium coelestinum, an eastern native that is popular with parasitoid wasps.[DOI:10.1016/j.biocontrol.2011.05.002] It is also an arms supplier to monarch butterflies, who harvest pyrrolizidine alkaloids from its nectar.[DOI:10.1111/een.13051]
2022-08-27 Gunner's Lake, Germantown, MD
A pretty plant that packs a punch. AKA touch-me-not, Impatiens capensis seeds disperse explosively when you touch the seed pod, flying up to two meters. Interior struts are pumped with water and kept in check by the skin (turgor pressure: the same mechanism that stiffens plant stems and other things). The struts curl when the pod is popped, slinging the seeds with the force of spring steel. Surprisingly, most seeds don't fly very far since they don't start in the right position, with only 0.5% of the potential energy being transferred on average. Evolution is clearly not optimizing for dispersal distance.[DOI:10.1093/jxb/erp070]
Note that jewelweed soap is sold as a traditional remedy for poison ivy rash, but it works no better than soap without jewelweed.[DOI:10.1016/j.jep.2014.12.024] Many thanks to those who volunteered for a two week bout of poison ivy to answer this question!
2022-08-27 Gunner's Lake, Germantown, MD
Mmmmm, aphids... These brown lacewings lay their eggs near an aphid colony and four days later a new aphid cleanup crew is born. After a week of gorging the larva will spin a cocoon, emerging as an adult after another week (or maybe next spring if the weather turns). Five weeks eating aphids as an adult and that generation is over. Note that M. subanticus are themselves controlled by a parasitic wasp (Anacharis sp) so different brown lacewings are used for biological control.[DOI:10.1093/aesa/61.5.1212] Twenty cents a piece at bugsforgrowers.com (sold out).
2022-09-02 Bethesda, MD
What big eyes you have! They are very distinctive; why are there so few of you on iNat (8) or BugGuide (5)? Sure, you are a parasitic wasp whose children eat live caterpillars for breakfast, but this should make you a celebrated member of the agroecological biological control force. A sibling species (O. scabricula) is listed as a beneficial invasive accidentally introduced to BC from Europe. DOI:10.4039/n07-011
2022-09-02 Bethesda, MD
Though it may look like a fierce predator, no need to worry unless you are a strawberry (and even then it will only take a few seeds). Like many insect species, Myodocha serripes plays host to symbiotic bacteria, sectioning off a part of the gut so they can survive. In return the bacteria clean up waste and act as small vitamin factories. First noted in 1809, these details are available because it is somebody's job to dissect and image the guts of insects, nowadays with nanometer resolution! [DOI:10.1002/jmor.21000]
2022-09-02 Bethesda, MD
An ecosystem is a complex web with (chain) links between different species. Consider grassland restoration inside the ring at Fermilab,[1] with staged planting, controlled burns and even some bison to disturb and fertilize the soil. Given that aggressive species will colonize newly disturbed soil, the question is why they give way to specialized plants. There appear to be feedback loops between soil organisms and the plants, with the first succession succumbing to soil pathogens, giving room for the next succession. It eventually reaches a steady state where soil and plants are mutually supportive and no species is overcrowded.[2]
2022-09-03 Bethesda, MD
[1] Betz, et al. (1996). Two decades of prairie restoration at Fermilab. No. FNAL/C-96/440; CONF-9610263-1. [2] DOI:10.1890/ES14-00480.1
This could be Sporobolus heterolepis (Prairie dropseed), one of a dozen grasses found in the tall grass prairie. As well as looking pretty against the purple backdrop it is a drought resistant native that provides seeds for birds in the fall.
2022-09-03 Bethesda, MD
Despite the Hollywood portrayal of bug vision as a multifaceted mess there are neural layers that process the raw inputs and put together a consistent image of the world. The simplest compound eyes absorb off-axis light, giving the equivalent of a retinal image with one pixel per lens. Others have non-overlapping fields of view for each lens, which are combined to a single view in the insect brain. For dim light fliers the fields of view can overlap between neighbours, with secondary neurons combining the overlapping pixels into one bright pixel.
2022-09-03 Bethesda, MD
A fixture in the clock repair shop, he likes to sit by the window and watch the passers-by. Apparently parrots can be trained to go potty, which is easier than washing guano off of old clocks. If you get a breeding pair you probably won't see the female much. She will find some hidden cubby to call home. In the wild she would spend up to 11 months a year in the nest, raising three sets of chicks. Her mate would do the foraging, bringing back food for her and her young. Or mates — nesting spots are limited so they are sometimes polyandrous with cooperating males.
2022-09-03 Bethesda, MD
Reflections on Bethesda. With each window pointing in a different direction this provides a view of downtown reminiscent of cubism. Bug eyesare also a series of “panes” on a convex surface, though with many more panes and many fewer pixels per pane. The glass has some flex, adding a bit of warp to the scene. This despite being poured flat on a bed of molten tin giving an even thickness and a smooth finish to each pane (Wikipedia).
Like a solar-powered roomba, Cicindela sexguttata wanders its patch of sunlight vacuuming up any insects flying overhead and digging springtails out of the leaves. Being an ectotherm it is dependent on the sun to raise its body temperature to 32C for foraging. Too hot and it "stilts", lifting its body off the ground to get airflow underneath. (I use a pair of pencils under my laptop to keep the fan from turning on.) Above 35 C and it runs for the shade. Adults live four years, using their deep larval burrows to survive Minnesota winters. DOI:10.1046/j.1365-2311.1998.00154.x
2022-04-24 McKee-Beshers WMA, Poolesville, MD
The early bird gets the (sand) worm. Snails, insects or crustaceans are also on the menu when available.
2022-09-13 New Smyrna Beach, FL
A proper double rainbow welcomed us to Florida, a bright inner arc formed by reflection from the back of the raindrop and another and a dimmer outer arc formed by a second reflection [Wikipedia]. We found neither gold nor pot.
2022-09-11 I95 south of Jacksonville, FL (Photo by Jay)
What a lot of teeth! Long and thin like an eel, it sneaks up from the side and lunges at high speed to complete its attack. To escape predators it has been known to leap out of the water and skitter over the water. Surf boards, for example, look dark and dangerous floating on the surface, which is how a Brazilian surfer wound up at the doctor's office with a needlefish jaw embedded in his ear (10.1016/j.wem.2020.03.009).
2022-09-13 Blackpoint Wildlife Drive, Merritt Is NWR, Titusville, FL
* Or maybe a redfin.
A pollinator whose larva feeds on crop pests. What's not to love? It does require some changes to current farming practices. You need refugia where the predators can live when there are no pests to eat (10.32530/jaast.v4i2.165). Kind of like a capacitor to filter the dynamic predator-prey oscillator, damping pest numbers toward zero. You need to be selective with whatever pesticides you do use. Many will indiscriminately kill beneficial insects along with pests leaving you unprotected when the residue disappears (10.1093/amt/tsz094) New buzzword: agroecology. Together with soil management and other techniques you can actually reduce costs and increase yield (10.1007/978-3-319-90309-5_8).
2022-09-11 DQ parking lot, Darien, GA
Strophostyles helvola on the beach. Not normally a salt-loving plant (halophyte), it gets increased salt tolerance from a symbiotic fungus infecting its roots (DOI:10.1023/A:1009844125905). In exchange for substantial amounts of sugar the fungus provides soil nutrients such as phosphorus and defends against pathogens. This relationship goes back to the earliest plants to venture onto land.[Wikipedia]
2022-09-15 New Smyrna Beach, FL
Ipomoea pes-caprae (worm-like goat's foot) showing its glorious flowers in the morning light. In addition to its numerous medicinal applications (DOI:10.3390/md20050329), it is an important beach stabilizer, appearing early on new dunes with deep roots and long trailing vines. Seeds sprout more readily after "scarification", with their coats ripped off by the action of wind and waves grinding them into the sand. Much better than sprouting in the middle of the ocean!
2022-09-15 New Smyrna Beach, FL
A bean weevil on beach morning glory (Ipomoea pes-caprae). She will lay her eggs on the seed pods and her larvae will bore into the seeds. Although a portion of the seeds are sacrificed in the process, bean weevils are efficient pollinators and likely coevolved (other insects cannot tolerate the alkaloids in the seeds). Seeds can travel up to six months in the ocean, spreading to tropical beaches around the world, but the beetles are restricted to the americas. DOI:10.1002/j.1537-2197.1989.tb15171.x
2022-09-15 New Smyrna Beach, FL
Catching the morning sun, one of a dozen Felis catus were hanging out near our hotel. Despite their reputation as aloof, gathering in a colony of this size is typical. Outdoor cats are pretty hard on the environment, being directly responsible for a number of extinctions. Cute but deadly. DOI:10.1002/fee.1633
2022-09-11 Manning, SC
Staking out territory on an algal mat, a prime spot for laying eggs. Like other dragonflies, his wings are made from a pair of membranes over a network of stiff veins. The membranes are primarily chitin (a sugar polymer similar to cellulose) with a waxy coating to keep them dry. Nanopillars act as antimicrobials, tearing apart the cell walls of bacteria and fungi. Corrugations provide additional strength. Pigments between the membranes give him his uniform amber-coloured wings.
2022-08-27 Gunner's Lake, Gaithersburg, MD
Insect Wings (wikipedia) DOI:10.1016/j.jcis.2021.06.093
They may be able to see in colour but they don't necessarily see well. Males will chase anything vaguely like an amberwing out of their territory, including horse flies and butterflies. DOI:10.1023/A:1012223217250
2022-09-12 St. Francis Trail, DeLand, FL
Don't get into a staring contest with a dragonfly: it won't blink. Instead it sheathes its receptor cones with pigment grains to protect against bright light. Most dragonflies have three color sensors, centered on UV, blue and yellow. The UV is concentrated in the eyes pointing upward, giving sharp silhouettes to anything flying overhead (it may be missing in Libellula needhami). The retinal cells from all the eyes feed into a "target tracking" neuron, with active suppression of distractors in the visual field leading to attention blindness.
2022-09-13 Scrub Ridge Trail, Merritt Is NWR, Titusville, FL
DOI:10.1007/BF00298040 DOI:10.1007/s13127-012-0090-6 DOI:10.1523/JNEUROSCI.1431-19.2019
Wearing a black mourning cloak while zipping along the water: widow skimmer. Alas, skimming did not evolve with modern conveyance in mind. Along with the low-flying common whitetail and green darner they are over-represented on the grills of cars by a factor of two to four. DOI:10.1016/j.biocon.2011.02.015
Happy New Year!
2022-08-13 National Zoo, Washington, DC