Daohan "Rex" Jiang

@rexjiang

Evolutionary biologist. Postdoc @oistedu.bsky.social. Evolutionary theories, complex traits, macroevolution. Views are my own. Website: iNaturalist:

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Daohan "Rex" Jiang@rexjiang· 2d

A #nest of #Okinawa mud #wasp (Delta esuriens) I've been observing for ~2 weeks. I saw the wasp working on it and it expanding over time. The last photo was taken today; it survived the most recent #typhoon.

A potter wasp is working on a nest on the wall of a building.

A potter wasp nest. The upper left conner has an opening, from which some Lepidoptera larvae can be vaguely seen.

A potter wasp nest, sealed and taller than before.

A potter wasp nest. It has expanded further along the wall.

Daohan "Rex" Jiang@rexjiang· 5d

A year of typhoons…🌀

Daohan "Rex" Jiang@rexjiang· 24d

I was only able to see the animal from a distance. Here’s a specimen displayed in an insect & art exhibition at @oistedu.bsky.social.

Specimen of a large butterfly. It has white wings with black spots and stripes. It’s mounted on a wooden base on which a butterfly’s wing pattern is carved.

Daohan "Rex" Jiang@rexjiang· 24d

Encountered this rice paper #butterfly (Idea leuconoe) today. This is the prefecture butterfly of #Okinawa and the largest butterfly here, with a wingspan of 12-14cm.

Daohan "Rex" Jiang@rexjiang· Jul 6

My 1st wild #octopus 🐙 sighting Apparently feeding on a #crab 🦀

Daohan "Rex" Jiang@rexjiang· Jul 2

It's the season of blueberry hermit crab (Coenobita purpureus) now. Today I encountered a shell-less one on the beach. No jettisoned shell 🐚 nearby either. Hope it can find a nice new home soon. #Okinawa #HermitCrab #Crustacean

A blue hermit crab without a snail shell on a sandy beach.

Daohan "Rex" Jiang@rexjiang· Jun 27

Well.

Daohan "Rex" Jiang@rexjiang· Jun 25

I’m trying to be like this guy lol

A teenager named Ikoma (protagonist Kabaneri of the Iron Fortress) is being infected by a kind of zombie virus after being attacked by a zombie-like creature known as Kabane. Most of his body is transformed into zombie. He is trying to hang himself to stop the virus from passing through his neck and spreading into his brain.

Daohan "Rex" Jiang@rexjiang· Jun 22

More! All near the west coast of #Okinawa. Common box crab (Calappa hepatica) Perplexing fiddler crab (Austruca perplexa) Tawny hermit crab (Coenobita rugosus), found in a forest near the sea. Scylla serrata, found near where a water canal joins the sea.

A box crab hiding in shallow water. It’s partially buried in sand. There is seagrass in the surrounding water.

On the right is a male fiddler crab with black-and-white body and a large, brightly colored left claw. On the right, there is another fiddler crab partially hiding in a burrow.

A hermit crab dwelling in a broken snail shell 🐚, held by a hand.

Daohan "Rex" Jiang@rexjiang· Jun 22

I’m obligated to post some new 🦀 sightings, ain’t I? This time it’s a dimorphic pair of tetragonal fiddler crabs (Gelasimus tetragonon)..,

Daohan "Rex" Jiang@rexjiang· Jun 20

A screenshot, in case you want a closer look at the cute 🦇!

Daohan "Rex" Jiang@rexjiang· Jun 20

Encountered a Ryukyu flying fox 🦇 (Pteropus dasymallus) today and luckily managed to film it this time #bat #flyingfox

Daohan "Rex" Jiang@rexjiang· Jun 9

Greetings from Eriphia sebana (Well, just an excuse to share new crab 🦀 clip)

Daohan "Rex" Jiang@rexjiang· May 20

I walked back home today, which is much slower than the shuttle bus but allowed me to encounter some cool creatures, like this colorful #beetle. Probably Sophiodela okinawana (I didn’t find its English common name), a tiger beetle #endemic to #Okinawa.

A beetle with a vibrant color scheme consisting of green, red, dark blue, and white areas.

Daohan "Rex" Jiang@rexjiang· May 19

They’re gorgeous! (And I believe @jopabinia.bsky.social must agree)

A specimen of a Japanese spider crab displayed in the Shanghai Natural History Museum. According to the sign, it was captured from the Tokyo Bay in 1896 and once in the collection of the Royal Asiatic Society, before eventually transferred to the Shanghai Natural History Museum.

Daohan "Rex" Jiang@rexjiang· May 6

Of course, adorable intertidal creatures as well…

A goby, likely an ornate sandgoby (Istigobius ornatus) in an intertidal pond.

Brittle stars in an intertidal pond. Their body disks are hidden in little holes on the rock, with ringed tentacles stretching out.

A black sea cucumber in an intertidal pond. Part of its body is stretched out, and its mouth is slightly unfolded.

Daohan "Rex" Jiang@rexjiang· May 6

Reward after a depressingly rainy golden week in #Okinawa: double rainbow 🌈 🌈

Daohan "Rex" Jiang@rexjiang· Apr 23

Barbary lions were from Africa, but Smilodon did have their own buddy lion Panthera atrox

Daohan "Rex" Jiang@rexjiang· Apr 22

I happen to have some nice Argiope photos too… An A. aemula just caught a Syntomoides imaon (a moth w/ partially transparent wings). Taken in Okinawa, Japan.

Daohan "Rex" Jiang@rexjiang· Apr 11

Thank you for your insight! Here are some more photos of #1.

Daohan "Rex" Jiang@rexjiang· Apr 10

Some adorable #crabs 🦀 seen today in the #intertidal zone.

Daohan "Rex" Jiang@rexjiang· Mar 25

Another goose barnacle bottle that appears to have drifted from China: it’s a kind of liquor that’s popular in China.

Goose barnacles attached to a glass bottle on a beach.

Label on a glass bottle to which goose barnacles are attached. The label indicates that the bottle was for erguotou (二锅头) wine, a popular kind of wine in China, with 56% alcohol by volume.

Daohan "Rex" Jiang@rexjiang· Mar 24

Just received the new articulated T. rex 🦖 from #PNSO. This time a reconstruction with lip. Looking forward to more 1:35 scale action figures from this line…

Daohan "Rex" Jiang@rexjiang· Mar 9

Our model explains various types of evolutionary convergence characterized by different degrees of difference between ancestral states of different lineages & between genetic bases of their convergent phenotypes. Hopefully this study could help us better think about convergence & predictability! 7/7

Daohan "Rex" Jiang@rexjiang· Mar 9

The constraint on expression program diversification is conditioned on conservation of the phenotypic effects of the regulators. If their effect can change (e.g., origin of new cis-elements), the decline of expression program diversity with complexity dampens. 6/n

Variance in regulator expression across species at the end of the
simulation, plotted against d_selection (blue), compared to the corresponding curve from simulations with constant C (black curve and dots; the same as those in Fig. 1C).

Daohan "Rex" Jiang@rexjiang· Mar 9

A key factor is the optimal phenotype's complexity (dimensionality): a very complex optimum can only be produced by a limited range of expression programs, so selection forces lineages toward the same solution; otherwise, each lineage evolves a solution that's close to the ancestral state. 4/n

Figure 1: (A-B) Schematic illustrations for the evolution of novel regulator expression programs in response to selection on the phenotypic state. Axes represent two principal components of regulator expression. Red curves with arrows represent trajectories of evolution in different lineages. (A) The optimal state can be produced by various regulator expression programs, which fall along the gray line. Independent lineages (species) that evolved under the same regime of selection ended up at different points along the line, resulting in variation in regulator expression across lineages. (B) The optimal state can only be produced by a specific regulator expression program, which is represented by the gray dot. Different species evolved towards the only solution and there is little variation in expression programs among them. (C-D) Relationship between evolution of the regulator expression program and complexity of the optimal phenotypic state (quantified by
the number of traits subject to selection, d_selection). (C) Variance in regulator expression across species at the end of the simulation, plotted against d_selection. (D) Divergence from the ancestral expression program at the end of the simulation, averaged across species and plotted against d_selection. Each data point in (C) and (D) corresponds to a simulated scenario where a unique set of traits were under selection. Each curve in (C) and (D) is a locally estimated scatterplot smoothing (LOESS) curve, with the gray area representing the 95% confidence interval (CI). Cell images representing optimal phenotypes in (A) and (B) are from Irasutoya (https://www.irasutoya.com/.)

Figure 2: (A-B) Schematic illustrations for two-stage evolution of novel regulator expression programs. Blue curves with arrows represent trajectories of neutral evolution in stage 1 (before phenotypic traits of interest are subjected to selection), whereas red curves with arrows represent trajectories of evolution in stage 2 (after selection is imposed). (A) The optimal state can be produced by various regulator expression programs (gray line). (B) The optimal state can only be produced by a specific regulator expression program (gray dot). (C-D) Relationship between evolution of the regulator expression program and complexity of the optimal phenotypic state (d_selection). Notations are the same as Fig. 1C-D, unless stated otherwise. (C) Variance in regulator expression across species at the end of stage 2, plotted against d_selection. Red dashed line represents expression variance right before selection is imposed (at the end of stage 1 and the beginning of stage 2). (D) Divergence from the expression program at the end of stage 1, averaged across species and plotted against d_selection.

Daohan "Rex" Jiang@rexjiang· Feb 26

Finally received the Spinosaurus book by @davehone.bsky.social & @markwitton.bsky.social. It arrived shortly after S. mirabilis was, kinda like how the T. rex 🦖 book narrowly “missed” the revival of Nanotyrannus. It’s hard to keep up with new work 😂

Daohan "Rex" Jiang@rexjiang· Feb 16

A comparison of the spiky beetle Acantholophus and the ankylosaur Borealopelta, the latter represented by a Kaiyodo gacha figure. Part of the insect art exhibition at @oistedu.bsky.social. Weirdly, the sign only refers to Zuul. Perhaps a different gacha should have been used.

Specimen of a beetle of genus Acantholophus and a miniature figure of a Borealopelta.

The sign with Japanese and English descriptions of the displayed item.

Two ankylosaur mini figures on my shelf. On the right is Borealopelta. The left one is Zuul, which the sign in the last picture referred to.

Daohan "Rex" Jiang@rexjiang· Feb 6

Some cool intertidal zone animals seen yesterday, before sunset. #goby #SeaCucumber #Okinawa

A goby, likely a frillfin goby (genus Bathygobius), in shallow water of intertidal zone.

A Black Sea cucumber (Holothuria leucospilota) in shallow water of intertidal zone. Oral tentacles are extended.

Daohan "Rex" Jiang@rexjiang· Jan 24

Some trophies from my recent #paleo #gacha figure hunt…