F Rosa Rubicondior: Evolution
Showing posts with label Evolution. Show all posts
Showing posts with label Evolution. Show all posts

Saturday 18 May 2024

Creationism in Crisis - A Spiny-Legged Arachnid From Over 300 Million Years Before 'Creation Week' - Giving Creationists Nightmares


Reconstruction of the 308-million-year-old arachnid Douglassarachne acanthopoda from the famous Mazon Creek locality.
Credit: Paul Selden
Ancient arachnid from coal forests of America stands out for its spiny legs | KU News

The technical term for the fear of learning that creationists seem to suffer from, is 'sophophobia' (from the Greek for knowledge or wisdom (sophia) and fear (phobia)). Their other manifest fears are 'atelophobia' (literally, a fear of being wrong) and theophobia (fear of gods).

Combine those acute anxiety disorders with arachnophobia (fear of arachnids or more precisely spiders) and sesquipedalophobia (fear of long words) and you can begin to understand why creationists can never be induced to read science papers like this one, which describes a fossilised arachnid with heavily-armoured, spiky legs from about 308 million years ago, that scientists have named Douglassarachne acanthopoda.

If anything is designed to deter creationists from reading about it, it is a fearsome arachnid with a long name that would make any creationists imaginary 'friend' really angry if they learned about it and might even make them wonder if they could be wrong. What could be more terrifying for a creationist?

So, creationists should either stop reading now, or find a responsible adult to be with them, because this describes how and where this 308 million-year-old fossil was found and how it fits in with what we know of the evolution of the arachnids, which includes spiders, mites, harvestmen, tics and the sister group, scorpions.

The fossil was found in shale in a coalmine spoil tip at Mazon Creek, Illinois, USA by palaeontologists Paul Selden from the University of Kansas and the Natural History Museum of London and Jason Dunlop from the Museum für Naturkunde Berlin. They have written up their discovery in an open access paper in the Journal of Palaeontology and describe it in a University of Kansas news release:

Ancient arachnid from coal forests of America stands out for its spiny legs

More than 300 million years ago, all sorts of arachnids crawled around the Carboniferous coal forests of North America and Europe. These included familiar ones we’d recognize, such as spiders, harvestmen and scorpions — as well exotic animals that now occur in warmer regions like whip spiders and whip scorpions. But there were also quite bizarre arachnids in these habitats belonging to now extinct groups. Even among these stranger species now lost to time, one might have stood out for its up-armored legs. The ancient critter recently was described in a new paper published in the Journal of Paleontology, co-written by Paul Selden from the University of Kansas and the Natural History Museum of London and Jason Dunlop from the Museum für Naturkunde Berlin.

Douglassarachne acanthopoda comes from the famous Mazon Creek locality in Illinois and is about 308 million years old. This compact arachnid had a body length of about 1.5 centimeters and is characterized by its remarkably robust and spiny legs — such that it is quite unlike any other arachnid known, living or extinct.

Professor Paul A. Selden, lead author.
Gulf-Hedberg Distinguished Professor Emeritus
Department of Geology
University of Kansas, Lawrence, Kansas, USA

The KU researcher said Carboniferous Coal Measures are an important source of information for fossil arachnids, representing the first time in Earth’s history when most living groups of arachnids occurred together. Yet, the fauna was still quite different to today.

Spiders were a rather rare group, only known at that time from primitive lineages, and they shared these ecosystems with various arachnids which have long since died out. Douglassarachne acanthopoda is a particularly impressive example of one of these extinct forms. The fossil’s very spiny legs are reminiscent of some modern harvestmen, but its body plan is quite different from a harvestman or any other known arachnid group.

Jason A Dunlop, co-author
Museum für Naturkunde,
Leibniz Institute for Evolution and Biodiversity Science
Invalidenstraße, Berlin, Germany.
This led the two scientists to conclude it doesn’t belong in any of the known arachnid orders.

Unfortunately, details such as the mouth parts cannot be seen, which makes it difficult to say exactly which group of arachnids are its closest relatives. It could belong to a wider group, which includes spiders, whip spiders and whip scorpions. Whatever its evolutionary affinities, these spiny arachnids appear to come from a time when arachnids were experimenting with a range of different body plans. Some of these later became extinct, perhaps during the so-called ‘Carboniferous Rainforest Collapse,’ a time shortly after the age of Mazon Creek when the coal forests began to fragment and die off. Or perhaps these strange arachnids clung on until the end Permian mass extinction?

Professor Paul A. Seden.
According to the team, Mazon Creek fossil locality is one of the most important windows into life in the late Carboniferous, producing a wide range of fascinating plants and animals. The present fossil was discovered in a clay-ironstone concretion in the 1980s by Bob Masek and later acquired by the David and Sandra Douglass Collection and displayed in their Prehistoric Life Museum.

The genus name Douglassarachne acknowledges the Douglass family, who kindly donated the specimen to the Field Museum of Natural History in Chicago for scientific study once it became apparent that it represented an undescribed species. Then, acanthopoda refers to the unique and characteristic spiny legs of the animal.

Jason A. Dunlop.

Abstract
A new genus and species of arachnid (Chelicerata: Arachnida), Douglassarachne acanthopoda n. gen. n. sp., is described from the late Carboniferous (Moscovian) Coal Measures of the Mazon Creek Lagerstätte, Illinois, USA. This is a unique animal with distinctive large spines on the legs. It has a subovate body, a segmented opisthosoma, and a terminal anal tubercle. The legs are robust and appear to have been similar in construction throughout the limb series, with heavy spination of the preserved proximal podomeres. The mouthparts and coxo-sternal region are equivocal. The preserved character combination does not permit easy referral to any known arachnid order, living or extinct, thus the new fossil in placed as Arachnida/Pantetrapulmonata incertae sedis. It contributes to an emerging pattern of disparate body plans among late Carboniferous arachnids, ranging from anatomically modern members of living orders through to extinct taxa, such as the present fossil, whose phylogenetic position remains unresolved.

UUID: http://zoobank.org/b70f5f95-9c8b-4389-bee5-b6031bff2ee2


Non-technical Summary
The forests of the late Carboniferous period (about 300–320 million years ago) harbored a great variety of arachnids. In addition to the familiar spiders, harvestmen, and scorpions, there were other, stranger kinds of spider-like animals. Here, we describe a large spider-like arachnid with very spiny legs (presumably to deter predators), from the world-famous Mazon Creek fossil localities of Illinois, USA.

Introduction
The late Carboniferous Coal Measures of North America and Europe offer an important window into the early evolution and diversity of arachnids. As well as hosting groups that are known from older deposits, namely scorpions (Scorpiones) and harvestmen (Opiliones), which have Silurian and Devonian representatives, respectively, the Coal Measures also yield the oldest records of several arachnid orders, namely spiders (Araneae), whip spiders (Amblypygi), whip scorpions (Thelyphonida), tick spiders (Ricinulei), and camel spiders (Solifugae) (for a recent overview of oldest records see Garwood and Dunlop 2023a, table 1). In addition to living arachnid groups, the Coal Measures also host three extinct orders: Trigonotarbida (known from the Silurian to the Permian), Phalangiotarbida (Devonian–Permian), and the monotypic Haptopoda (Carboniferous). What is also becoming apparent (e.g., Garwood et al. 2016; Selden 2021) is that there are several Coal Measures fossils of ostensibly spider-like animals that were sometimes initially placed in Araneae, but which lack the key character of silk-producing spinnerets. The impression is that several arachnid fossils of this age belonged to extinct lineages whose position in relation to the established orders has yet to be resolved.

The Mazon Creek Fossil-Lagerstätte is rightly famous for the abundance of marine and non-marine fossil biota found in clay ironstone concretions that are collected from the spoil heaps of the old strip mines around Braidwood in northeastern Illinois (Selden and Nudds 2012) (Fig. 1.1, 1.2). These localities have yielded fossils of all the extant and extinct arachnid orders listed above (e.g., Meek and Worthen 1868; Scudder 1868.1, 1884, 1890; Melander 1903; Petrunkevitch 1913, 1945; Selden 1992), with the exception of Haptopoda, which has only been found in the British middle Coal Measures. The new fossil from Mazon Creek is evidently something very different from any previously described arachnid from either this or any other Coal Measures locality. It is characterized by its distinctive habitus of an ovate body and robust and very spiny legs. The preserved character combination makes it difficult to place the fossil in any known arachnid order (see below), but it is described and named here with comments on its possible affinities.
Figure 1. Type locality and stratigraphy for Douglassarachne acanthopoda n. gen. n. sp. (1) Locations of strip mines and dumps from shafts in the Mazon Creek area; Pit 15 Northern Mine shown in bold at bottom right; (2) map showing the location of (1) in Illinois; (3) stratigraphic log of the Francis Creek Shale Member and associated members of the Carbondale Formation, with position of concretions in lower part of Francis Creek Shale Member emphasized in bold (map and log based on Baird et al.1986).
Geological setting
The specimen was found at the spoil heap of Pit 15 Northern Mine near Essex, Kankakee County, Illinois, coordinates: 41.1525°N, 88.2275°W (Fig. 1). The fossil-bearing concretions occur in the Francis Creek Shale Member of the Carbondale Formation, which overlies the Colchester No. 2 Coal Member, and is itself overlain by the Mecca Quarry Shale Member (Selden and Nudds 2012; Clements et al. 2019); the concretions are generally found towards the base of the Francis Creek Shale Member (Fig. 1.3). Based on the Mazon Creek flora containing elements comparable to those in the late Asturian Substage of Western Europe, and the dating of ash beds associated with cyclothems in Europe and North America (Montañez et al. 2016.1), the age of the coal and overlying shale member of the Mazon Creek area is now established to be between 308.6 and 308.4 million years old.
Figure 2. Douglassarachne acanthopoda n. gen. n. sp., holotype and only known specimen FMNH PE 91366. (1) Photograph of part; (2) explanatory drawing of part; (3) photograph of counterpart; (4) explanatory drawing of counterpart; 1–4 = leg numbers; a t = anal tubercle; e t = eye tubercle; fe = femur; t = tergite. Scale bars = 5 mm.
Figure 3. Douglassarachne acanthopoda n. gen. n. sp., holotype and only known specimen FMNH PE 91366; for interpretative drawings and scale, see Figure 2. (1) Part, detail of distal femur and more-distal podomeres, showing nature of curved macrospines on lateral edge of distal podomeres, bases of macrospines on dorsal surface of femur; (2) counterpart, detail of posterior opisthosoma showing bilobed structure at base of anal tubercle.


Imagine being raised by fundamentalist, creationists parents who will have taught you that a magic mind-reading thug in the sky, who has an especially nasty punishment for you if you have the wrong thoughts, and that you mustn't learn anything that might make you doubt the literal truth of the Bible, and because of your limited, creationist education, you probably wouldn't understand it anyway, it's easy to understand why creationism results in such ignorance of science and even depends on it, and why parents and creationist cult leaders actively discourage learning.

But ignorance doesn't create truth, of course, and the facts are still there whether creationists know and understand them or not. So, when creationists do manage to overcome those psychological barriers; those irrational phobias that are designed to keep them ignorance, they are free to discover a fascinating and infinitely interesting world, not just in the present, but in the history and historical forces that shaped the present, and the who suddenly become much richer and rewarding that ever the Bronze Age authors of the Bible ever thought.

It is an enduring mystery why people who believe a god created the entirely of reality are so reluctant to discover it, in case that same god gets angry with them for learning about it.

Unintelligent Design - A Heath-Robinson Solution To A Simple Problem


Convolutriloba longifissura. The green body color of the adult comes from algal symbionts integrated in its skin. The red stripes in the middle of the body of this 3 millimeter long worm indicate mature oocytes.

Credit: Eric Rottinger/www.Kahikai.org
National Science Foundation - Media Gallery
The surprising relationship between marine worms and the algae that live inside them | Stanford Report

Creationists who like to cite complexity as evidence of intelligent design, either don't understand design or believe the designer is a bumbling idiot who never settles for a simple solution when a more complicated one is available, and never misses an opportunity to make a mountain out a molehill, as my old mother used to say if we turned a small problem into a big one.

That's of course, if you believe that creationist superstition of magic creation and not the scientifically proven, evolution, as an explanation for the form of living things.

Imagine you're a creator who is designing a simple marine flatworm and you decide that just what it needs is to be able to make food the way plants do, using the energy in sunlight to turn carbon dioxide into sugars. You previously designed some bacteria to perform this process, then, in an earlier invention, you put some of these bacteria in a single-celled plant and made algae. You could have given the single-celled plant the same enzymes and metabolic pathway you gave the bacteria but that was too simple, so you put the bacteria inside the plant cell as cell organelles called chloroplasts.

Tell me all about the marine flat worm Convolutriloba longifissura, please. Convolutriloba longifissura is a species of acoelomorph worm that inhabits marine environments. Here are some key details about this fascinating organism:

Taxonomy and Classification
  • Kingdom: Animalia
  • Phylum: Acoelomorpha
  • Class: Acoela
  • Order: Acoelida
  • Family: Convolutidae
  • Genus: Convolutriloba
  • Species: Convolutriloba longifissura
Morphology and Anatomy
  • Size and Shape: Convolutriloba longifissura are small, flattened worms. They are typically only a few millimeters in length.
  • Body Structure: They lack a true gut and body cavity, characteristic of acoelomorphs. Instead, their digestive system consists of a simple gastrovascular cavity.
  • Symbiotic Algae: These worms often contain symbiotic algae within their tissues, which provide them with nutrients through photosynthesis. This relationship is beneficial for both the worm and the algae.
Reproduction
  • Asexual Reproduction: Convolutriloba longifissura is well known for its remarkable method of asexual reproduction, specifically through transverse fission. The worm can split itself into two or more parts, each of which regenerates into a complete organism. The name "longifissura" hints at this long splitting process.
  • Regeneration: Post-fission, each segment is capable of regenerating the missing parts, making this species a subject of interest in the study of regenerative biology.
Habitat
  • Marine Environment: These worms are found in marine environments, often associated with coral reefs and shallow coastal waters. They prefer habitats where they can benefit from their symbiotic algae.
Behavior
  • Locomotion: Convolutriloba longifissura moves using cilia on its ventral surface, gliding smoothly over substrates in its habitat.
  • Feeding: The diet consists mainly of small particles and microorganisms. Their symbiotic relationship with algae also plays a crucial role in their nutrition.
Ecological Role
  • Symbiosis and Ecosystem Interaction: As part of the marine ecosystem, they play a role in nutrient cycling and serve as a food source for other marine animals. Their relationship with symbiotic algae also contributes to primary production in their habitats.
Research Significance
  • Regeneration Studies: The ability of Convolutriloba longifissura to regenerate its body parts makes it an important model organism in scientific research, particularly in studies related to developmental biology and regenerative medicine.
  • Evolutionary Insights: Studying this worm provides insights into the early evolution of bilaterian animals, given its position in the phylogenetic tree.
Conservation Status
  • Population and Threats: There is limited information on the conservation status of Convolutriloba longifissura specifically. However, like many marine organisms, they could be affected by habitat degradation, pollution, and climate change.
Fun Fact
  • Bioluminescence: Some species within the Convolutriloba genus are known for their bioluminescence, although it is not well-documented if Convolutriloba longifissura exhibits this trait.
In summary, Convolutriloba longifissura is a small but remarkable marine worm notable for its asexual reproduction through fission, its symbiotic relationship with algae, and its significance in scientific research on regeneration and evolutionary biology.
But what about these flatworms?

You now have three choices: you can give them the same enzymes and processes you gave the bacteria, but that was too simple for the algae, so why make it that easy for the flatworm? You could put the bacteria in the flat-worm cells like you did with the algae; but why do that when there is an even More complicated method? The third choice is to put the algae inside the flatworms and, as that's the most complicated way of doing it, why not go for that solution?

Friday 17 May 2024

Creationism in Crisis - How Baobab Trees Evolved and Dispersed Over 21 Million Years


Madagascan baobab trees.
The origin and long-distance travels of upside down trees - Queen Mary University of London

The baobab or 'upside down' trees, mostly of Madagascar, are an interesting example of how species radiate and evolve to fit different available niches in their immediate environment, but the genus also contains some examples of remarkable migrations and one example of the founder effect in evolution where a new species can arise by going through a very narrow genetic bottle neck where a new population is founded on an atypical sample of the parent species genome.

The evolution of the genus also includes examples of how, as species diverge, there is a period during which they can still hybridize and how hybrids themselves can be the foundation of new species.

Creationism in Crisis - Dinosaurs Evolved Warm-Bloodedness 180 Million Years Before 'Creation Week'


First ‘warm-blooded’ dinosaurs may have emerged 180 million years ago | UCL News - UCL – University College London

Of all the different orders of living organisms' only mammals and birds today are warm-blooded, i.e., they are able to maintain a body temperature, within a certain range of ambient temperatures, by either producing heat or losing it, as necessary.

It might be thought that this indicates that the ability evolved in a common ancestor but of the ancestors of birds, the evidence suggests that many dinosaurs were cold-blooded like today's reptiles, and mammals are descendants of an earlier, pre-dinosaurian reptiles, so these similar processes for maintaining the body temperature may be more a matter of convergence than common ancestry.

Do mammals and birds use the same method to maintain their body temperature, and if not, how do they differ? Mammals and birds both maintain their body temperatures through endothermy, meaning they generate and regulate heat internally to keep their body temperatures stable. However, there are differences in how they achieve this due to variations in their physiology and behaviors. Here’s an overview of the similarities and differences:

Similarities in Temperature Regulation
  1. Metabolic Heat Production:
    • Both mammals and birds generate heat through metabolic processes. This involves breaking down food to produce energy, with heat being a byproduct.
  2. Insulation:
    • Both groups have evolved insulating layers to retain heat. Mammals have fur or hair, while birds have feathers. These layers trap air and provide a barrier against the cold.
  3. Shivering Thermogenesis:
    • Both can generate additional heat through shivering, which involves rapid muscle contractions that produce heat.
  4. Behavioral Adjustments:
    • Both mammals and birds engage in behaviors to manage their temperature, such as seeking shade or shelter, sunning themselves, or altering their activity levels based on the ambient temperature.
Differences in Temperature Regulation
  1. Physiological Mechanisms:
    • Sweating and Panting: Mammals often use sweating and panting to cool down. Sweat glands secrete moisture that evaporates, taking heat away from the body. Dogs, for instance, pant to evaporate moisture from their respiratory tract. Birds, on the other hand, do not sweat. Instead, they often rely on a behavior called gular fluttering, where they rapidly move the skin in their throat to increase evaporation and cool down.
    • Brown Adipose Tissue (BAT): Many mammals, especially small ones and those living in cold environments, have brown adipose tissue that generates heat through non-shivering thermogenesis. Birds lack this type of tissue.
  2. Heat Exchange Systems:
    • Countercurrent Heat Exchange: Birds have highly efficient countercurrent heat exchange systems in their legs and feet, which minimize heat loss. Blood vessels are arranged such that warm arterial blood warms the cooler venous blood returning to the body, conserving heat. While some mammals also use countercurrent heat exchange (such as in extremities), the systems are particularly pronounced and crucial in birds.
  3. Basal Metabolic Rate:
    • Birds generally have higher basal metabolic rates compared to mammals of similar size, which means they produce more heat relative to their body size. This higher metabolic rate is partly due to the high energy demands of flight.
  4. Hibernation and Torpor:
    • Many mammals can enter states of torpor or hibernation to conserve energy and reduce body temperature during periods of cold or food scarcity. While some birds also enter torpor, true hibernation is rare in birds. Instead, some birds migrate to warmer regions to avoid cold weather.
Behavioral Differences
  1. Migration:
    • Migration is a key strategy for many birds to avoid extreme temperatures. While some mammals also migrate, it is far more common and pronounced in birds.
  2. Nesting and Roosting:
    • Birds often build insulated nests or seek out warm roosting spots to maintain body temperature, especially during breeding seasons or cold nights. Mammals, on the other hand, may use burrows, dens, or other insulated shelters.
In summary, while both mammals and birds use endothermic processes to maintain their body temperatures, the specific physiological and behavioral strategies they employ can differ significantly due to their distinct evolutionary paths and physical characteristics.
A team of researchers led by University College London (UCL) and Universidade de Vigo, Spain, scientists has concluded that dinosaurs may have evolved warm-bloodedness as long ago as 180 million years ago, some 50 million years after the first dinosaurs evolved.

They concluded this after relating the evolutionary tree of the dinosaurs throughout the Mesozoic era to climate and geographical changes over the same time period and examining 1000 dinosaur fossils.

Their findings are the subject of an open access paper in the Cell Press journal, Current Biology. Their work is also explained in a UCL news release:
The ability to regulate body temperature, a trait all mammals and birds have today, may have evolved among some dinosaurs early in the Jurassic period about 180 million years ago, suggests a new study led by UCL and University of Vigo researchers.
In the early 20th century, dinosaurs were considered slow-moving, “cold-blooded” animals like modern-day reptiles, relying on heat from the sun to regulate their temperature. Newer discoveries indicate some dinosaur types were likely capable of generating their own body heat but when this adaptation occurred is unknown.

The new study, published in the journal Current Biology, looked at the spread of dinosaurs across different climates on Earth throughout the Mesozoic Era (the dinosaur era lasting from 230 to 66 million years ago), drawing on 1,000 fossils, climate models and the geography of the period, and dinosaurs’ evolutionary trees.

The research team found that two of the three main groupings of dinosaurs, theropods (such as T. rex and Velociraptor) and ornithischians (including relatives of the plant eaters Stegosaurus and Triceratops), moved to colder climates during the Early Jurassic, suggesting they may have developed endothermy (the ability to internally generate heat) at this time. In contrast, sauropods, the other main grouping which includes the Brontosaurus and the Diplodocus, kept to warmer areas of the planet.

Previous research has found traits linked to warm-bloodedness among ornithischians and theropods, with some known to have had feathers or proto-feathers, insulating internal heat.

Our analyses show that different climate preferences emerged among the main dinosaur groups around the time of the Jenkyns event 183 million years ago, when intense volcanic activity led to global warming and extinction of plant groups. At this time, many new dinosaur groups emerged. The adoption of endothermy, perhaps a result of this environmental crisis, may have enabled theropods and ornithischians to thrive in colder environments, allowing them to be highly active and sustain activity over longer periods, to develop and grow faster and produce more offspring.

Dr Alfio Alessandro Chiarenza, first author
Centro de Investigación Mariña
Departamento de Ecoloxía e Bioloxía Animal
Universidade de Vigo, Vigo, Spain

And Department of Earth Sciences
University College London, London, UK.

Theropods also include birds and our study suggests that birds’ unique temperature regulation may have had its origin in this Early Jurassic epoch. Sauropods, on the other hand, which stayed in warmer climates, grew to a gigantic size at around this time – another possible adaptation due to environmental pressure. Their smaller surface area to volume ratio would have meant these larger creatures would lose heat at a reduced rate, allowing them to stay active for longer.

Dr Sara Varela, Co-author
Centro de Investigación Mariña
Departamento de Ecoloxía e Bioloxía Animal
Universidade de Vigo, Vigo, Spain.
In the paper, the researchers also investigated if sauropods might have stayed at lower latitudes to eat richer foliage unavailable in colder polar regions. Instead, they found sauropods seemed to thrive in arid, savannah-like environments, supporting the idea that their restriction to warmer climates was more related to higher temperature and then to a more cold-blooded physiology. During that time, polar regions were warmer, with abundant vegetation. The Jenkyns event occurred after lava and volcanic gasses erupted from long fissures in the Earth’s surface, covering large areas of the planet.

This research suggests a close connection between climate and how dinosaurs evolved. It sheds new light on how birds might have inherited a unique biological trait from dinosaur ancestors and the different ways dinosaurs adapted to complex and long-term environmental changes.

Dr Juan L. Cantalapiedra, co-author
Departamento de Paleobiología
Museo Nacional de Ciencias Naturales (CSIC), Madrid, Spain.
The study involved researchers from UCL, University of Vigo, the University of Bristol and the Museo Nacional de Ciencias Naturales in Madrid, and received funding from the European Research Council, the Spanish Ministry of Research, the Natural Environment Research Council and the Royal Society.
Highlights
  • Warm-blooded dinosaurs flourished in varied climates.
  • Dinosaur groups adapted differently to climate, suggesting diverse thermophysiologies.
  • Endothermy in theropods and possibly ornithischians evolved by the Early Jurassic
  • Sauropod niche conservatism suggests higher thermal sensitivity and poikilothermy.

Graphical Abstract
Summary

A fundamental question in dinosaur evolution is how they adapted to long-term climatic shifts during the Mesozoic and when they developed environmentally independent, avian-style acclimatization, becoming endothermic.1,2 The ability of warm-blooded dinosaurs to flourish in harsher environments, including cold, high-latitude regions,3,4 raises intriguing questions about the origins of key innovations shared with modern birds,5,6 indicating that the development of homeothermy (keeping constant body temperature) and endothermy (generating body heat) played a crucial role in their ecological diversification.7 Despite substantial evidence across scientific disciplines (anatomy,8 reproduction,9 energetics,10 biomechanics,10 osteohistology,11 palaeobiogeography,12 geochemistry,13,14 and soft tissues15,16,17), a consensus on dinosaur thermophysiology remains elusive.1,12,15,17,18,19 Differential thermophysiological strategies among terrestrial tetrapods allow endotherms (birds and mammals) to expand their latitudinal range (from the tropics to polar regions), owing to their reduced reliance on environmental temperature.20 By contrast, most reptilian lineages (squamates, turtles, and crocodilians) and amphibians are predominantly constrained by temperature in regions closer to the tropics.21 Determining when this macroecological pattern emerged in the avian lineage relies heavily on identifying the origin of these key physiological traits. Combining fossils with macroevolutionary and palaeoclimatic models, we unveil distinct evolutionary pathways in the main dinosaur lineages: ornithischians and theropods diversified across broader climatic landscapes, trending toward cooler niches. An Early Jurassic shift to colder climates in Theropoda suggests an early adoption of endothermy. Conversely, sauropodomorphs exhibited prolonged climatic conservatism associated with higher thermal conditions, emphasizing temperature, rather than plant productivity, as the primary driver of this pattern, suggesting poikilothermy with a stronger dependence on higher temperatures in sauropods.

Dinosaurs have always been a problem for creationists because their existence betrays the fact that the age of Earth as calculated from the Bible geneaolgies is wildly inaccurate by several orders of magnitude, but this paper piles on the agony by showign a clear evolutionary pathway from poikilothermy (cold-bloodedness) to homeothermy (warm-bloodedness) supported by geological, geographical and climatological evidence sometime around 180 million years before the biblical 'Creation Week'.

And it goes without saying that, being biologists, the authors of the paper show no sign of abandoning the TOE in favour of the childish notion of magic creation by an unproven supernatural entity. Indeed, they could scarcely be considered scientists if they included magic and superstition in their explanation for natural phenomena like creationists pseud-scientists are obliged to for contractual reasons.
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Thursday 16 May 2024

Evolution News - How Tiger Beetles Have Evolved an Unusual Form of Batsian Mimicry - Or Is This Unintelligent Design?


Tiger beetle, Lophyra sp.

Tiger beetles fight off bat attacks with ultrasonic mimicry – Research News

The idea of predator-prey arms races is of course entirely inconsistent with the childish notion of intelligent design, because constantly designing solutions to problems you created earlier as solutions to even earlier problems you created, is not an act of intelligence.

And yet creationists continue to believe in intelligent [sic] design despite the abundance of these competitive arms races in the natural world.

It seems they have no difficulty in holding several pairs of mutually contradictory views of their putative designer god simultaneously. It is supremely intelligent and acts in ways that can only be described as supremely stupid.

It is omnibenevolent but designs ways to increase the suffering in the world with its parasites; it is omnipotent but powerless against another supernatural designer called 'sin'; and by the way, it is the only supernatural entity capable of designing living thing, so 'evidence' of design (i.e. something a creationist can't understand how it could have evolved) is proof of its existence.

Malevolent Designer News - Has Creationism's Divine Malevolence Designed An Improved Version of Cholera?


Vibrio cholerae
Persistent Strain of Cholera Defends Itself Against Forces of Change, Scientists Find - UT News

One of the mysteries of microbiology and epidemiology, is why a virulent strain of Vibrio cholerae (the bacterium that causes cholera) has remained so stable ever since it emerged in 1961 in Indonesia, causing the seventh global cholera pandemic. this strain, known as 7PET, is now the predominant strain, out-competing the other strains and infecting an estimated 1.3 - 4 million people a year, of which between 21,000 and 143,000 die.

The reason for those wide-ranging estimates is because many of the deaths from cholera are in remoter areas of mostly third-world countries where sanitation is poor, health-care is hard to obtain, and many of the victims are children, so the cause of death is often not known with any certainty.

The traditional response of creationists to anything concerning the evolution of parasites like V. cholerae is to blame 'Sin'. The more sophisticated creationists who have realised that this is a blasphemy because it implies the existence of another creator over which their supposedly omnipotent, omni-benevolent god is powerless, so they simply blame this 'sin' thing for allowing 'genetic entropy' to cause an organism to 'devolve' (it would be a serious blasphemy to call it 'evolution' so Michael J Behe and the Deception Institute had put their heads together and come up with the term 'devolution' instead, which makes it look like the exact opposite of 'evolution'. Stupidly, this devise claims that everything was created perfectly and, when Adam & Eve 'sinned', somehow this opened the door to 'sin', which apparently took their 'omniscient' god by surprise, even though it had given its alleged creations immune systems in anticipation of the effects of 'Sin'.

But of course, we can dismiss that half-baked notion which no serious biomedical scientist would take seriously because there is no mechanism for a deleterious (i.e, 'devolutionarly' trait to accumulate in the species gene pool, and whatever it is about V. cholerae that gives it the edge over other strains, can't rationally be described as 'devolutionary', or a move away from some notional initial perfection, because there can't be anything better than perfect, and yet the 7PET strain of V. cholerae is better at doing the two things it appears to have been designed to do - making more people sick and making more copies of itself than the other strains.

Monday 13 May 2024

Evolution in Progress - How Two Isolated Populations in Papua New Guinea Have Diverged


Genetic adaptations have impacted the blood compositions of two populations from Papua New Guinea | Tartu Ülikool

An example of evolution if progress this week comes from a team of researchers from the universities of Tartu (Estonia), Toulouse (France), and Papua New Guinea. They have carried out an extensive analysis on blood samples from two populations in Papua New-Guinea who have remained isolated for the 50,000 years since Homo sapiens arrived on the Island.

One group occupies the highlands and the other group lives in the lowlands, making this a living laboratory to measure the effects of the different environments on the genomes of the two populations.

Different environments provide different drivers of evolutionary adaptation; for instance, the highlanders have adapted to a low oxygen partial pressure and comparatively few pathogens and an absence of mosquitoes; while the lowlands have both mosquitoes and a higher level of endemic pathogens. How each group has adapted to these different environments provides a text-book example of how the environment drives evolution and how isolation results in divergence.

The team's work is published, open access, in Nature Communications and is explained in a press release from Tartu University, Estonia:

Sunday 12 May 2024

Common Ancestry - How Young Chimps Learn To Use Tools - Just Like Human Children


Wild western chimpanzee using a stick tool to extract high-nutrient food.

Credit: Liran Samuni, Taï Chimpanzee Project (CC BY 4.0)
Protracted development of stick tool use skills extends into adulthood in wild western chimpanzees | PLOS Biology

Chimpanzees are famous for making and using tools, especially sticks, for obtaining nutritional foods like grubs and termites, but using them takes time, just like a human child needs to develop motor skills to use tools such as pens and pencils with sufficient dexterity.

How they do so, and the stages they go through, was described recently in an open access paper in PLOS Biology by a team of animal behaviourists from l'Institut des Sciences Cognitives Marc Jeannerod (The Marc Jeannerod Institute of Cognitive Sciences), Lyon, France; the Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany, and the German Primate Center, Göttingen, Germany, who analyzed film of wild chimpanzees making and using stick tools in the Taï National Park, Côte d’Ivoire.

They concluded that, like human children, acquiring motor skills is not just a matter of practice, important though that it, but also depends on a protracted childhood during which they observe and copy adults with the necessary skills. In other words, young chimpanzees learn skill from their parents and elders, like a human apprentice.

The team's work was explained in information made available ahead of publication by PLOS, and published in SciTechDaily.com:

Friday 10 May 2024

Unintelligent Designer News - How Creationism's Idiot Designer Continually Designs Different Solutions To The Same Problem


Squinting bush brown, Bicyclus anynana

© Judy Gallagher (CC BY-SA)
New sex-determining mechanism in African butterfly discovered - News - University of Liverpool

Once sexual reproduction had become established in multicellular organisms, there was selection pressure to determine the gender of a developing embryo, so the result was either genetically male or genetically female. In humans and other mammals, for example, this is achieved by the XY Chromosomes, which, unlike all the other chromosomes (autosomes) are not paired. A zygote with 2X (homozygous) becomes a female and a zygote with XY (heterozygous) becomes male. Because the zygote gets either one or the other of these chromosomes from each parent these are the only combinations possible, so we never see a YY zygote.

Thursday 9 May 2024

Malevolent Design - Combatting The Highly Toxic, Tissue Destroying Spitting Cobra Venom


Black-necked spitting cobra, Naja nigricollis
© Marius Burger, CC0, via Wikimedia Commons
First effective treatment found for spitting cobra snakebite - Lancaster University

Snake venom is usually a potent cocktail of multiple different toxins, 'designed' to kill, mostly small vertebrate prey very quickly, so the snake can strike, then wait for the prey to become paralyzed or die before it can go very far.

The reason for this rich cocktail is an interesting piece of evolutionary biology that would embarrass any creationist with the courage to learn about it. It is the result of repeated arms races between the snake and its prey species. Not only that, but it involves new genetic information arising, by gene duplication and mutations - contrary to creationist dogma that such a thing is impossible.

As one prey species starts to evolve resistance there is selection pressure on the snake to change its venom to overcome the resistance or loose one source of food, but, there must be a balance between retaining one food species but loosing several others if the changed venom is less effective against them. Resistance usually arises when there is a change in receptor sites on cell surfaces, on which the venom acts so the active venom molecule doesn't bind to it.

Tuesday 7 May 2024

Malevolent Design - How Creationism's Divine Malevolence Co-opted Red Squirrels To Spread Leprosy in Medieval England


Mycobacterium leprae
Ancient Mycobacterium leprae genome reveals medieval English red squirrels as animal leprosy host: Current Biology

Few places in Europe or elsewhere were more pious than Medieval England, but still creationism's pestilential malevolence continued to make people suffer with diseases such as bubonic plague, tuberculosis and the related leprosy. Even the extreme measures taken by believers to atone for imaginary transgressions that had brought about the Black Death had failed to assuage the putative designer god who was believed to be visiting this pestilence upon people.

The superstitious Bible-based belief in evil spirits and 'sin' as the cause of disease led to the social stigma that made the disease so feared and led to the isolation of sufferers in lepper colonies, and often reduced to begging to stay alive. Poor nutrition and poor sanitation led to a worsening of the condition and, although these counter-measures were visibly ineffective, such was the belief in the Bible that it was inconceivable that the disease could be caused by anything other than 'sin' and evil demons being permitted to enter the victim.

The modern equivalent of this victim-blaming superstition can be found in the modern creationist tactic of blaming 'Sin' and 'genetic entropy' for parasites, with demons being replaced by 'entropy' to make it sound sciencey. It is of course, Bible-based superstition without supporting evidence.

And now, if you believe that stuff, there is evidence that creationism's putative designer god designed M. leprae to also infect red squirrels so they would act as a repository to spread leprosy. Red squirrels were common in those days and were often captured in the wild for pets or pelts. Their skins, when used for clothing, would have carried M. leprae and infected anyone who wore them - a brilliant strategy, if you hate people and want them to be sick, suffer and die.

Monday 6 May 2024

Unintelligent Design News - How Creationism's Putative Designer 'Brilliantly' Designs Solutions To Problems It Supidly Designed


Two-spot spider mite (yellow form), Tetranychus urticae
Plants utilise drought stress hormone to block snacking spider mites | Sainsbury Laboratory

To start at the beginning because that's always a good place to start, plants need to get water and nutrients up to their leaves, so their 'designer' gave them a vascular system but without a pump, so, to maintain the upward flow, they need to evaporate away (or transpire) the water that just arrived in their leaves. They do this through tiny pores (or stomata; singular=stoma) that are just about visible to the naked eye, and clearly visible under a hand lens or a microscope.

These stomata are guarded by guard cells, one on either side, which can swell to close the stoma or shrink to allow the stoma to open, as the need arises.

However, these stomata are an open invitation to sap-sucking arthropods such as mites and aphids, which are cleverly designed, reputedly by the same designer that designed the stomata, which can push their mouthparts into the stoma to get at the nutrient-rich watery contents of the leaf.

So, having designed these sap-suckers to exploit the transport system it designed for plants, creationism's putative designer clearly saw the sap-suckers it had designed as a problem to be solved.

How it added this Heath-Robinson layer of additional complexity to solve the problem the earlier layer of complexity had caused is the subject of a research paper by a collaboration of researchers from the Centre for Plant Biotechnology and Genomics (CBGP), Spain, and Sainsbury Laboratory, Cambridge University (SLCU), Cambridge, UK and a news release from Cambridge University:

Malevolent Designer News - How Creationism's Favourite Pathogen Is Designed to Cause UTIs



UTI's will affect 50% of women at some time in their lives
How E. coli get the power to cause urinary tract infections | Michigan Medicine

Despite their protestations that their god doesn't create pathogens - some other creative entity does that, apparently - they have been in love with Escherichia coli, or E. coli ever since their guru and Deception Insitute flunky, Michael J Behe, persuaded them that he had 'proved' their god exists and designs things because he couldn't work out how the E. coli flagellum could have evolved - so God did it!

There problem then, courtesy of Michael J Behe is that they have accepted that, if there was a designer involved in E. coli's design, it is the god that Michael J Behe 'proved' designed it, so their god designs pathogens, and even designs clever way to make them good at making us sick.

With that in mind, which creationist is going to argue against Michael J Behe's clever 'proof' that their god designs things so must exist, and insist that it isn't also behind the newly discovered way it manages to cause urinary tract infections (UTIs)?

The discovery that they can live, reproduce, and do their nasty thing in the otherwise near-sterile urinary tract, was made by researchers at the laboratory of Professor Harry Mobley in the University of Michigan Medical School.

Having been filtered by the kidneys, while urine contains some chemicals such as metabolites, it is about as sterile as it gets, with anything in it entering through the urethral meatus, in women, stupidly placed near the anus and inside the vulva where it can become infected during sexual intercourse by a penis cleverly designed with a foreskin to harbour pathogens under.

It has now been discovered that E. coli is also cleverly 'designed' to grab the nutrients it needs but can't manufacture itself by have a highly efficient transport system for taking them from its victims at a rate of thousands of molecules a second. One of the genes responsible for this, codes for an enzyme known as ATP-binding cassette (ABC).

Typical of creationism's 'intelligent' [sic] designer, if you believe in such a thing, is the Heath-Robinson workaround for the lack of genes for manufacturing these amino acids, where the parasite needs an energy-intensive ATP-based transport system, complete with multi-layered back-up systems to keep them working - the needless waste and needless complexity, so typical of evolved systems and the antithesis of intelligently designed systems. The researchers have published their findings, open access, in the journal PNAS and explained them in a University of Michigan news release:
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