Javier Abalos

It is out, it is out! Our study on neural crest cells and micro to macroevolution in lizard skull 🦎

Before trips to Mars, we need better protection from cosmic rays High-energy particles streaming through space can damage DNA and increase cancer risk, but antioxidants, tardigrades and hibernation could help astronauts make the journey safely.

High-energy particles streaming through space can damage DNA and increase cancer risk, but antioxidants, tardigrades and hibernation could help astronauts make the journey safely.

How does development shape skull evolution? In lizards, neural crest–derived skull bones drive rapid sexually selected shape change within species but show long-term constraint, revealing developmental bias linking micro- and macroevolution. Image Credit: Wikimedia
academic.oup.com/evlett/advan...

Throat coloration in common wall lizards (Podarcis muralis). From top to bottom: White morph with the characteristic green and black coloration of the nigriventris syndrome; White morph with the ancestral brown phenotype; yellow and orange morphs from populations where individuals show varying expression of the nigriventris characters.

Two new Science studies on lizard coloration reveal how a delicate interplay of genetics, environment, and social dynamics can either preserve or erase polymorphic diversity in species.

📄: https://scim.ag/4srYKHi
📄: https://scim.ag/4qCcsWn

🧪 Check this if you are interested in the convoluted evolution of lacertid colours. Yes, I know, we missed a unique opportunity opportunity to call the phenomenon "Chromatic Barrier of the Appennines", which totally sounds like a badass DnD spell.
#evolution #colsci #lizard #sexualselection

A general signalling theory: why honest signals are explained by trade-offs rather than costs or handicaps Abstract. Honest signals have long posed a challenge for evolutionary biologists to explain. Here we propose a general Darwinian theory of signalling, Sign

🦚🔪"The Handicap Principle [HP] is the only theory in modern biology to our knowledge that is anti-Darwinian... The time is long overdue to reject HP/costly signalling paradigm... the longest non-Darwinian detour in the history of modern biology"

Reptiles, los grandes olvidados: cómo mejorar su bienestar ayuda a cambiar su mala imagen Tenemos una percepción estereotipada de los reptiles como animales extraños y poco inteligentes que no se corresponde con la realidad y que puede influir en el trato deficiente que reciben en cautivid...

Se acaba de publicar cierto artículo de la ganadora del I concurso de comunicación científica de la @ucciuv.bsky.social, @bartolomealicia.bsky.social #ciencia #divulgacion #reptiles #bienestaranimal
theconversation.com/reptiles-los...

Hi Eryn, I would love to be added to the evolutionary biologist feed. I am Javier Abalos, postdoc researcher on lizard coloration and behaviour. Evidence: scholar.google.es/citations?us...

An Aplysia sea slug, also called sea hares

Today I found out that the sex pheromones of Aplysia (a genus of extremely large sea slugs) are called:

• Enticin 🌶️
• Attractin 👁️🫦👁️
• Temptin 🌺
• Seductin 🔥

And I find that wonderful. Please vote for your favorite. Credits to Trystam Wyatt's book on Pheromones and Animal Behavior.
#ethology

Thanks for this thread, what an eye-opening funny study. When will the plot stop thickening with evolution??

🦎THREAD: We just published something wild in @asn-amnat.bsky.social - lizards missing entire limbs not only survive, but some appear to actually thrive in the wild?!

Let me tell you about the "three-legged pirate" lizards 🏴‍☠️

[Paper: www.journals.uchicago.edu/doi/10.1086/... ]

(1/n)

As forests are cut down, butterflies are losing their colours The insects’ brilliant hues evolved in lush ecosystems to help them survive. Now they are becoming more muted to adapt to degraded landscapes – and they are not the only things dulling down

Check this piece published on @theguardian.com featuring the awesome work of an international team (pics by @rgarciaroa.bsky.social lens) on butterflies 🦋 coloration and deforestation 🌲🪓 in the Amazon

As forests are cut down, butterflies are losing their colours www.theguardian.com/environment/...

Round 4 of surveys for the Mt Lyell #salamander (Hydromantes platycephalus). We were able to sample 7 salamanders this time, including a juvenile! #herpetology #herps #amphibians

A white-fronted bee-eater (Merops bullockoides) decides whether to consume a warningly colored white-barred acraea butterfly (Telchinia encedon). Photo (c) Mike Rowe

📢🦋 Our paper ‘Global selection on insect antipredator coloration’ is out and featured on the cover of @science.org

We ran a huge experiment to find out how ecological context favours camouflage and warning colouration as antipredator strategies. 1/6

www.science.org/doi/10.1126/...

Many wall lizards briefly sport bright blue tails as predator decoys after hatching. Our new study shows their throats and bellies also change color, yet at wavelengths invisible to humans! Could other species, too, undergo such cryptic shifts?
@uv.es @ucciuv.bsky.social
tinyurl.com/4rjfmde9
🧪🦎

10 lizards were smuggled into Cincinnati in a sock. Now there are tens of thousands. Native to Europe, common wall lizards are growing bigger, faster, and more resilient in Ohio. Scientists say the city itself may be driving their evolution.

Thrilled to see *National Geographic* highlight the wall lizards living in Cincinnati and our research on these little guys!
www.nationalgeographic.com/animals/arti...
#WalliesWorld

Watch #BiologyLetters author Avery Maune talk about new research revealing that urbanization can reshape social behaviour in the common wall lizard (Podarcis muralis): cassyni.com/events/3Hp2U... #AnimalBehaviour #ethology

Protección frente al alarmismo agrario: la tortuga mora, rehén del ruido político en la Región de Murcia El plan de conservación de esta especie ha encendido un fuego cruzado en el campo: mientras científicos y ecologistas reclaman medidas urgentes para salvarla, Vox agita el miedo entre los agricultores...

Protección frente al alarmismo agrario: la tortuga mora, rehén del ruido político en la Región de Murcia www.eldiario.es/1_c103ac?utm...

Gobierno Vasco suspende la campaña de la pesca de la angula de 2025-2026 ante la situación "crítica" de la especie El Departamento de Alimentación, Desarrollo Rural, Agricultura y Pesca del Gobierno Vasco se ha reunido...

ESTO ES IMPORTANTÍSIMO
Euskadi suspende la campaña de la pesca de la angula ante la situación crítica de la especie
Un paso crucial para lo conservación de la anguila, tomada en el territorio donde su consumo tiene más arraigo
@miteco.gob.es y otras CCAA, os toca
www.europapress.es/euskadi/noti...

Universidad de Valencia La UV, fundada en 1499, es una de las universidades más antiguas de España. Es una universidad pública, moderna e innovadora orientada a la docencia y a la investigación en casi todos los ámbitos del ...

Aquí podéis encontrar una nota de prensa sobre nuestro ultimo artículo. Muchas gracias al equipo de @ucciuv.bsky.social
#divulgacion #lagartijas #color #desarrollo

www.uv.es/uvweb/univer...

Influence of weather conditions, prey size and abundance, flight height and dialects on population trends, habitat selection and the spatial distribution inferred from bat acoustic activity obtained with passive acoustic monitoring. The dashed arrows represent possible biases that should be investigated in the future.

📖Published📖

Roemer et al. propose a comprehensive evaluation of the limits and possibilities of passive acoustic monitoring of bats, identifying knowledge gaps and practice barriers, and highlighting novel ideas that may revolutionise practices🦇👇

buff.ly/l8DGN7X

🌍 🧪

Energy conversion efficiency peaks at intermediate flight speed in a migratory songbird Using in vivo measurements of thrush nightingales flying in a wind tunnel, Macias-Torres et al. show that energy conversion efficiency varies with airspeed following a concave function, with a maximum...

After a lot of time spent in the darkness of the wind tunnel, the results finally see the light.
I'm very excited to share what will become the first chapter of my thesis.
Energy conversion efficiency peaks at intermediate flight speed in a migratory songbird www.cell.com/current-biol...

A young Podarcis muralis lizard doubts before crossing a crevice using a grass blade as a bridge. The first of many challenges he will face growing up!

Our discovery reveals a hidden stage in lacertid colour development that reshapes how we understand animal coloration as a signal, reminding us how central development is in communication and sexual selection across nature.

Adult Podarcis muralis lizards rest on top a log during a mesocosm experiment.

These colour changes may let juveniles avoid costly aggression or courting from adult males, while sparing adults wasted effort on non-competitors/immature mates. As lizards grow, greater colour differentiation may aid recognition and help stabilize social networks.

Adult males of Lilford's wall lizard (Podarcis lilfordi) from the island of Aire, close to Menorca. Two males are facing each other on yop if a log while adopting a raised-body posture that exposes the UV-reflecting spots and acts as a threat behavioral display.

Could these changes be adaptive? Predation avoidance often explains juvenile colour shifts, but in P. muralis that’s unlikely. Instead, a social role seems more plausible: ventral colour is usually hidden, yet adults display throats & flanks in social encounters

Ontogenetic changes in Podarcis muralis throat coloration. (A) Pie charts represent the proportions of juveniles showing different throat colors (UV+w = UV+white, UV−w = UV−white, oo = orange, yy = yellow, ow = orange–white, yo = yellow–orange) in September (t1; 3–4 weeks after hatching), and June–July (t2; 1 year after hatching). The three pie charts correspond to the full data set of 417 hatchlings measured at t1 (purple), the subset of 66 surviving juveniles measured as hatchlings at t1 (green), and these same juveniles measured as yearlings in t2 (yellow). (B) Reflectance spectra from the 62 surviving yearlings showing pure color morphs (solid lines and shaded area represent means ± SEM). The dashed purple line represents the average throat spectra of 417 hatchling lizards (similar to that of the 62 surviving yearlings when first measured, see central pie chart). Spectra have been normalized by subtracting the minimum reflectance of each spectrum at all wavelengths. (C) Mean and CI95 of the chromatic and achromatic distances (dS and dL respectively) between paired measurements of throat reflectance (i.e., within-individual hatchling-yearling contrasts), separated by yearling throat color. JND stands for “Just Noticeable Differences”. Two dashed lines at 1 and 3 JNDs represent two theoretical discriminability thresholds. If the confidence interval of a point includes a discriminability threshold, the two colors are not distinguishable at this threshold according to receiver cone sensitivities and relative abundance.

By the end of their first year, most juveniles show adult-like ventral colours. But only some, mostly males, develop UV-blue spots on their flanks, and these look still very different from adult ones to conspecifics.

Ontogeny of ventral coloration in Podarcis muralis. (A) Representative photographs of ventral coloration in a hatchling lizard 2–3 weeks after hatching (left), and in four yearlings re-captured in March 2019 (7 months after hatching). SVL stands for snout to vent length in mm. (B) Young male of P. muralis showing incipient UV-blue and melanin-based black patches in the outer ventral scales (OVS). (C) UV photograph of a hatchling P. muralis lizard showing UV+white color in its ventral surface. (D) Paired UV and visible photographs of the same subadult female (< 1 year) showing UV−white in the throat and UV+white in the belly. The difference is only apparent in the UV image. Photographs in C and D were obtained with a full-spectrum camera and two filters, each transmitting light either in the visible (400–700 nm) or the near-UV (320–380 nm) range. Brighter areas in the UV image have higher UV reflectance (i.e., hatchling ventral surface and female belly).

We found:

🦎 Hatchlings look white to us, but reflect far more UV than adults.

🦎 This “UV+white” is distinct and visible to lizards.

🦎 Ventral colours and UV flank spots develop out of sync.

🦎 Males and females diverge in timing and pattern.

Juvenile common wall lizard hatching from the egg.

In our “new” study (it’s from 2018, research goes slowly…), we tracked wall lizards from hatching to one year of age. We reared them in semi-natural conditions, measured their colours using spectrophotometry, and modeled how other lizards perceive them.

Coloration in common wall lizard (Podarcis muralis). a) Alternative throat colours in males and females. b) Detail of UV-reflecting spots in the outer ventral scales. Extracted from Abalos et al., 2020 (https://doi.org/10.1002/ece3.6659)

Wall lizards (Podarcis if you're feeling fancy) are famed for dazzling color diversity matched by a UV-sensitive vision system. The widespread P. muralis shows ventral & lateral colors—including UV-reflecting spots and alternative throat colors— which likely play a role in social communication