07 de diciembre de 2023

DNA for Identification

What if results of DNA sequencing don't match result of morphology (eg. the organism's appearance in iNaturalist photos)?

The bits of DNA that are sequenced tell you a lot about the relationships between the bits of DNA. That often, but not always, tells about the relationships between the organisms. Why not? Most often, incomplete gene sorting. The population of the common ancestor included both variations in the DNA -- let's call them A and B. In the ancestors of one species, A was lost. In the ancestors of the other, most A was lost and B predominates, but A still exists in low numbers. Thus sampling any single individual can be misleading.

Other possibilities include past hybridization followed by backcrossing, or some kind of horizontal gene transfer. Also, even the best of labs can have occasional incidents of contamination. (Sorry, but that can't be completely excluded from just one run.) Also, though it isn't as much a problem now as in the early days of PCR, the PCR reaction can become highly biased if the first cycle copies some untypical DNA sequence, perhaps from an organism's surface or from its last dinner, and that gets amplified. Also, though I hate to say it, we have probably all mislabeled a photo from time to time.

People forget that DNA sequences are genetic markers but structures of teeth and genitalia and other structures, even many behaviors, are also genetic markers. So is color pattern (though it may be a highly variable genetic marker in some species). Relying on just one marker is a kind of shorthand, good enough in most cases but sometimes misleading.

Publicado el diciembre 7, 2023 04:09 TARDE por sedgequeen sedgequeen | 1 comentario | Deja un comentario

14 de julio de 2023

Correspond with a student through Letters to a Pre-Scientist

Letters to a Pre-Scientist is a program that pairs students (about 6th through 9th grade, but if varies) with people involved in science, technology, engineering, or math (professionals, grad students, etc.). It's a great program. It's sign-up time! Please participate! See https://prescientist.org/

Through the program, the student writes four letters (physical letters) to you over the course of the school year and you respond to each one. Many of the kids have never written or received a letter before. The hope is that you'll make science seem more accessible to the student, but just corresponding with an adult is a learning experience for them.

On-line training is required, some time in August.

All students in each class participate, so you may hear from excellent students or really poor ones. Classes are usually in financially stressed areas.

Please participate in this program.

Publicado el julio 14, 2023 05:17 TARDE por sedgequeen sedgequeen | 1 comentario | Deja un comentario

21 de junio de 2023

Show Me The Other Side!

When I'm trying to identify a willow observation, I may need to see the underside of the leaf, but too often no such view is provided. I can't reach through the internet to flip that leaf! I depend on you, the observer. Please flip it for me. Please. Below are some examples where seeing both sides is important.

Leaves. Show the upper and lower surface. For some species, we'd like the view of the lower surface to be close enough view to see the hairs. Of course, the camera may not cooperate with that.

Flowers. We all love beautiful photos of the front of a flower. However, identification may require information about the sepals or phillaries or the flower shape, so also get a photo of the side or back of the flower. (And don't forget to include leaf photos! The flower may not be enough for ID.)

Galls. Identification is much improved if we can see how the gall is shaped on both upper and lower side of the leaf. So flip the leaf and photo both sides.

Butterflies. Both the upper and lower side of butterfly wings may be useful for identification and if you don't know what genus it's in, you don't know which side is more important. So photo both sides if possible. Obviously, you can't flip a live butterfly over, but if you wait a bit, the butterfly may move enough that you can get a photo of top and bottom. (Sometimes the butterfly just will not expose both sides. Go ahead and post what you have. This is often enough for ID, but not always.)

Dead birds, snakes, turtles, frogs, etc. Animals are rarely polite enough to die with their most identifiable side up, so it the corpse is relatively fresh, photo the obvious side and then, please, use your foot or a stick to flip it, then photo that other side. Please do NOT flip and post really gross dead animals. (Or if you do post them, post something non-gross as the first photo, even if that's just a cropped picture of a bit its tail or toe.)

Mushrooms and shelf fungi. Seeing the top surface is important, of course, but we need to know if the fungus has gills or pores, and sometimes details of those structures, so please show the lower surface. A photo of the stem of the mushroom may be useful, too. You may need other, microscopic features, too, but that's another issue.

Lichens. Identification is likely to require seeing both top and bottom of any flat lichen.

Snails (including sea shells). Take three photos, showing the top, the bottom, and the side. The side photo should show the opening where the snail body is or was.

Slugs. Besides the top view, get one of the right side, the side with the opening slugs that breathe through. In a few cases, you need a photo of the bottom of the slug's foot, too, though I admit I usually don't disturb the animal that much.

Clams. If the clam is alive, make sure you get the side and the hinge area. If you're dealing with empty shells, get the outside and inside, making sure you show well the area near the hinge inside.

Different species may have different requirements for identification. In general, get at least two photos when possible, including a general view as well as close-up(s). That said, if you have an idea what it is, you may know that one view is important and others are not. We'll always try to ID with what you give us, but sometimes we do need your help to see more of the organism.

Publicado el junio 21, 2023 09:51 TARDE por sedgequeen sedgequeen | 8 comentarios | Deja un comentario

31 de mayo de 2023

Too much a botanist

"Stranded Tuber Rescued" cried the headline on the first page of the newspaper. I wondered, what species? How did it become stranded and what does that mean for a tuber? Why was it rescued; is it rare? Turns out the tuber was a man riding an innertube down a river. Aargh!

Publicado el mayo 31, 2023 02:03 TARDE por sedgequeen sedgequeen | 10 comentarios | Deja un comentario

12 de abril de 2023

Bamboo Identification in Oregon and Washington (preliminary)

So far, we have found five wild and quasi-wild bamboo in Oregon and Washington. They are Arrow Bamboo (Pseudosasa japonica), Broad-leaf Bamboo (Sasa palmata), and members of the genus Phyllostachys. Obviously, we will be very interested to see observations of additional species in our area.

Phyllostachys species have a groove or flat surface extending up the stem from one node to the next. The leaf sheaths low on the stems fall of early. They typically have 2 branches per node on the main stem. Pseudosasa japonica and Sasa palmata lack that groove and have persistent leaf sheaths. I think both have just one branch per node; I'm sure Ps. japonica does. Pseudosasa is a taller, sturdier species with small, narrow leaves (to 2 inches, 5 cm, wide). Sasa palmata is shorter and more slender and has broader leaves (to 3.5 inches, 9 cm, wide).

Although the name Common Bamboo (Bambusa vulgaris) is commonly applied to Oregon and Washington observations, it is not common and probably not escaping (if present) in these states.

Note: We're at the very beginning of the learning curve for bamboo identification. We're improving, but so far we have just enough knowledge to be dangerous, so take any ID's we make with a grain of salt.

[Edited April 16. We are learning.]

Publicado el abril 12, 2023 03:19 TARDE por sedgequeen sedgequeen | 0 comentarios | Deja un comentario

Bamboo in Oregon and Washington

My colleagues and I are trying to figure out which bamboo species are growing wild or quasi-wild in Oregon and Washington, and to map where they grow. Would you please help us by posting appropriate bamboo sightings in these two states?

We are most interested in wild bamboo that are spreading down waterways or were plants spread accidentally by human activities (earth moving, dumping yard waste). We also want to know about quasi-wild bamboo forming long-abandoned stands that have spread within their site (e.g. in abandoned home sites). We have some interest in plants that have spread from cultivation less extensively (e.g. into an adjacent road ditch or under a sidewalk), but we are not interested in clones that have spread a little in a garden or into adjacent property.

What to photo? (1) The whole plant. (2) The main stems, showing stem color, persisting leaf sheaths (if present), tops of those leaf sheaths, and color or structures at nodes. (Node = the thickened ring where leaves or branches originate.) A photo with your hand or some other standard can help tell how wide the main stems are. In one species here, the lowest few stem internodes (places between nodes) are very short, much shorter than most internodes; photo that if you notice it. (3) The number of branches that grow from one node on the main stem. (4) Leaf shape. (5) The bases of leaf blades, where there may be conspicuous hairs. Their presence or absence can be a useful clue for identification. (6) The rhizomes (horizontal stems) if visible, but no need to dig for them. (7) If you find new shoots growing up this year, photo the sheaths and those projections, vestigial leaf blades, that grow at the sheath tip.

Comments can help. Estimate plant height, if possible. (Or show a person standing near the bamboo, for scale.) Bamboo stems may be absolutely smooth, as if enameled, or may be minutely scabrous (rough). If rough, they may feel rough when running your hand up or down the stem or only one way. Please describe. Are the leaves green or glaucous (blue-green or gray-green) on the upper and/or lower surface?

Some wild stands have Bamboo Mites, genus Stigmaeopsis, (e.g. https://www.inaturalist.org/observations/152900504 ). These don't matter to our project, but they can give you a second observation at the site, if you want. Be careful not to spread the mites to cultivated bamboo stands.

Publicado el abril 12, 2023 03:17 TARDE por sedgequeen sedgequeen | 1 observación | 0 comentarios | Deja un comentario

30 de noviembre de 2022

On Identifying Queen Anne's Lace (= Wild Carrot = Daucus carota)

iNaturalist has over 14,000 "needs ID" observations of Daucus in North America, although we have only two Daucus species and one (D. carota) is abundant and usually easily identified. Please help get more of these identified!

Here are some things I learned when working on this.

A. Daucus carota has an array of tiny white flowers, the ones on the outer edges a little enlarged. Lots of other plants have the same pattern, so this by itself isn't enough for identification.

B. Daucus carota often has a dark purple flower in the very center. If present, this allows identification! (in North America) Its absence means nothing, though. Example: https://www.inaturalist.org/observations/143044211

C. The bracts at the base of the flower cluster (compound umbel) in Daucus carota are moderately long and have 3 to 7 slender lobes. Example: https://www.inaturalist.org/observations/142548223 This is unusual in North American members of the Carrot Family, so if the plant looks good otherwise, this will tip me over to identifying it as D. carota.

D. The nest-like structure formed as the seeds mature is distinctive -- the easiest way to identify Daucus carota! Example: https://www.inaturalist.org/observations/143284547 Late in the fall, the outer branches may spread out again. CAUTION: Visnaga daucoides, introduced to California and the Gulf Coast has slender nest-like fruiting heads, but each has a whole tangle of many, many bracts at the base and the seeds have very short bristles. CAUTION: In the native annual Daucus pusillus the fruiting structure is similar but flatter, more cup-like, and very dense, with shorter bracts with short lobes.

E. Daucus carota stems are coarsely hairy. That's not enough to identify one, but it it's smooth, it's not D. carota.

F. In the Carrot Family, leaves are often useful for identification. Unfortunately, Daucus carota leaves look a lot like those of some other species, including the weed Scandix pecten-veneris. (On the other hand, leaves that look like D. carota leaves and are posted as D. carota leaves usually are D. carota leaves . . . . )

Similar species:

The Texas endemic Daucosma laciniata has pinnately divided bracts and bractlets like Daucus carota. It differs in having much less divided leaves and glabrous fruits, and its inflorescences don't form a nest-like structure in fruit.

Daucus pusillus is smaller, lacks the purple center flower, and has more divided bracts that usually have blunt tips and are usually longer than the cluster of flowers or fruits. It grows on both coasts. It also grows along the Gulf Coast and north to at least Oklahoma.

Visnaga daucoides (= Ammi visnaga), introduced to California and the Gulf Coast has slender nest-like fruiting heads, but each has a whole tangle of many, many bracts at the base and the seeds have very short bristles.

Publicado el noviembre 30, 2022 07:39 TARDE por sedgequeen sedgequeen | 8 comentarios | Deja un comentario

16 de julio de 2022

Letters to a Pre-Scientist program

I strongly recommend the Letters to a Pre-Scientist (LPS) program. It connects 5th to 8th graders in certain poor U.S. schools (poor as judged by the percent of students who get free lunch) with college students and professionals in various fields of science, technology, engineering, and math (STEM). The student and his/her STEM pen pal exchange letters four times over the school year. The kids are really interested in this process, which is unlike anything else they do.

The program needs more STEM folks this year because it's expanding. I hope you will look into this and participate and/or share the information with others who may be interested. Registration to be a pen pal is now open!

Can you correspond in a language other than English? LPS tries to match students whose first language isn't English with STEM people who can use the same language.

A couple of notes: All students in the class participate, from the top to the bottom in scholarship. You can specify if you only want to correspond with the brightest, but remember that each student needs a pen-pal. Also, LPS tries to have more STEM people than students, so students can pick someone whose field sounds interesting. Therefore, each year some people don't get picked. But maybe next year! It's worth hanging around.

Here's information and a link from one of the LPS organizers:

Great news -- STEM professionals can register now to be pen pals during the 2022-2023 school year! 🎉

Letters to a Pre-Scientist connects students with real scientists through eight snail mail letters to demystify STEM careers, humanize STEM professionals, and empower all students to see themselves as future STEM professionals.

This will be our biggest year yet: we will match over 3,000 scientists with student pre-scientist pen pals! We're seeking passionate STEM professionals ready to broaden student's awareness of the possibilities that STEM has to offer.

With gratitude,

Lex
Program Manager, Pre-Scientist, Inc.

P.S. Share the pen pal registration link with other STEM professionals you know!

Publicado el julio 16, 2022 04:06 MAÑANA por sedgequeen sedgequeen | 2 comentarios | Deja un comentario

09 de mayo de 2022

Apology

I'm very slow to identify observations and respond to tags right now. I apologize. I'm currently very, very busy with an iNaturalist project plus another project plus spring. This will improve about June 12. Until then, all I can do is apologize.

Publicado el mayo 9, 2022 05:00 TARDE por sedgequeen sedgequeen | 2 comentarios | Deja un comentario

27 de febrero de 2022

An Ambitous Rat, Foiled

A female Bufflead took off running across the water. In the middle of the inlet she stopped and looked back ( https://www.inaturalist.org/observations/106387592 ). I couldn't see what was disturbing her, though a big of wood was floating in the water -- no, swimming! Swimming energetically toward her. What could it be? A pair of Mallards swam closer to investigate. If this mammal was trying to catch the Bufflehead, it ought to be an otter, but the amount of brown mammal visible above the water's surface was only about big enough for an otter's head. Size and the rapidly churning legs so close to the front end also ruled out nutria, muskrat, and beaver. Could this possibly be a rat? I think so! ( https://www.inaturalist.org/observations/106387593 )

While the Bufflehead kept a careful distance, the Mallards closed in on this intriguing object. They didn't actually touch it, but they kept close, especially the female Mallard. The rat gave up on the Bufflehead and turned back toward shore. The Mallards convoyed with it. The rat pulled out on a rock and groomed. It was kind of cute, actually, with big ears. (It's tail was longer than its head plus body, but never visible in its entirety except in brief glimpses I couldn't photo.) The rat jumped toward land, landing a bit short, and ran off into cover. What?? The perplexed female Mallard walked onto the land. She stood looking around for a long time. ( https://www.inaturalist.org/observations/106387594 ) Finally she gave up and joined her drake in the water.

This occurred in Waldport, in the part of the bay visible at the junction of Mill Street and Highway 34.

Publicado el febrero 27, 2022 12:32 MAÑANA por sedgequeen sedgequeen | 2 comentarios | Deja un comentario