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

Thursday 14 March 2024

Creationism in Crisis - Rice Paddy Snakes In Thailand Diversified About 2.5 Million Years Before 'Creation Week'


Hypsiscopus murphyi sensu
Photo: Bryan Stuart
Rice paddy snake diversification was driven by geological and environmental factors in Thailand, molecular data suggests | KU News

In one of those far-away places that the simple-minded authors of the story in Genesis about a small flat Earth with a dome over it being magicked up out of nothing in the Middle East, 10,000 years ago, could never have guessed existed, and some 2.5 million years before they though Earth existed, major environmental changes were driving the diversification of a species of snake into several descendant species, just as the Theory of Evolution predicts.

If those simple-minded Bronze Age pastoralists had known about it and understood its significance in terms of the history of life on Earth and the dynamic geology of the planet, just imagine how different their imaginative tale would have been! As it was, they had to do their best with what little knowledge and understanding they had.

The snake in question was the Rice Paddy snake, otherwise known as a mud snake, and the far-away place was Thailand where the rise of the Khorat Plateau caused environmental changes that resulted in the evolutionary diversification of the Hypsiscopus genus.

The team of researchers from various American and Southeast Asian Universities, who have shown this link between environmental change and evolutionary radiation in a genus was led by Dr. Justin Bernstein, of the University of Kansas Center for Genomics. Their findings are published open access in Scientific Reports and are explained in a Kansas University news release:

Wednesday 13 March 2024

How Science Works - Giraffes - A single Pan-African Species Or Several Distinct Species?


Reticulated giraffe, Buffalo Springs, Kenya. Photo: Mogens Trolle

Photo: Mogens Trolle
Gene flow in giraffes and what it means for their conservation – Department of Biology - University of Copenhagen

In an evolutionary picture that resembles that of humans, giraffes appear to have speciated, or partially speciates at different times and in different parts of their range, then hybridized, before splitting again with regular gene-flow between the groups.

Similarly, though over a greater range, humans seems to have partially speciated into isolated populations in Africa before coming together again and spreading to Eurasia as Homo erectus which then split into Neanderthals, Denisovans and possibly others before meeting up with H. sapiens coming out of Africa in a second wave, to interbreed with the Eurasian species. The result is genetically distinct populations with evidence of ancient hybridization and gene flow.

Because conservation efforts tend to be directed at the species level, it is important for giraffe conservation to determine whether there is a single pan-African species with local sub-species or whether there are four or more species, each with a smaller population and therefore more vulnerable to habitat destruction and extinction.

To try to resolve this issue, as part of the African Wildlife Genomics research framework led by research groups at the Department of Biology at the University of Copenhagen, scientist carried out an extensive genome analysis to establish whether the different populations have been genetically isolated for long enough to be regarded as distinct species, even though, in captivity, they freely interbreed.

The results were a little surprising but highlight the difficulty in determining whether speciation has occurred within a population where differentiation is still in progress and few barriers to hybridisation have arisen. The problem is compounded by the fact that there is not a fixed definition of species, although biologists understand what the term means in a given context.

I've previously written blog posts about this problem, using the Eurasian crows as an example - an article incidentally which was recommended reading for Scottish biology students doing their 'Highers'.

The researchers have published their findings open access in the online Cell Press journal, Current Biology and explain it in a news item from the University of Copenhagen Biology Department:

Thursday 7 March 2024

Creationism in Crisis - Evolution of Porcini Fungus


A tale of terroir: Porcinis evolved to the local environment – @theU
Structure of Fungi
This illustration is a little misleading because mycelia are often much larger than any of their mushrooms that appear on the surface of the soil or tree stumps. Fungi can grow up to a half a mile of the thread-like hyphae a day. In fact, the largest known organism on the planet is the Humongous Fungus (Armillaria ostoyae) in The Malheur National Forest, Oregon, measuring 2,385 acres (3.72 square miles) in area. It is estimated to be between 1900 and 8650 years old.
Photo credit: FoodPrint.org
The edible porcine fungus (Boletus edulis) also known as the boletus or penny bun is highly prized culinary delicacy throughout much of Europe. However, there is something strange about it evolution, especially in North America, according to a new report in the journal New Phytologist.

Creationists should note here that the scientists who produced the report see this 'problem' entirely within the Theory of Evolution by Natural Selection (TOE). The strangeness is not a problem for the theory but an example of how a fundamental principle of the theory - environmental selection - operates in North America.

The 'problem' is that while Boletus edulis exists in North America as a number of different varieties and genetically distinct populations, probably caused not so much by geographical isolation as environmental adaptation, albeit with regular ingress from surrounding populations, In Eurasia, a single genetic lineage dominates from Spain to Georgia to Scandinavia, so the interesting question is why does is the species genetically continuous in Eurasia but fragmented in North America; what is the difference between the two landmasses that causes this difference.

The Eurasian and North American populations are believed to have become separated during a period of climatic change and the onset of glaciation, 1.62–2.66 years ago. Attempts to segregate populations of Boletus edulis into distinct species based on phenotype have foundered on the genetic evidence, illustrating how small genetic differences can give large phenotypic differences and how a species in the process of speciating passes through a stage at which the diverging populations have not diverged sufficiently to qualify as new taxons because the practice of taxonomy tries to fit a continuous process into a series of distinct events.

The 'problem' is the subject of a free access paper in the journal New Phytologist by Keaton Tremble and Bryn T. M. Dentinger from Utah University, Utah, USA. together with J. I. Hoffman from Bielefeld University, Germany, and was described in a University of Utah press release:

Friday 23 February 2024

Creationism in Crisis - 250 Million Years of Butterfly And Moth Evolution


Butterfly and moth genomes mostly unchanged despite 250 million years of evolution

It'll no doubt come as a surprise to those creationists who believe Earth was created from nothing by magic just about 10,000 years ago to learn that the butterflies and moths have been evolving for 250 million years.

It'll maybe come as a bigger surprise to those creationists who have been fooled into believing that the Theory of Evolution is being discarded by mainstream biologists in favour of their childish fairy tale of magic and supernatural spirits, that yet another group of mainstream biologists regard it as the foundation of modern biology, and are participating in the Darwin Tree of Life Project, which aims to sequence the genome of 70,000 eukaryote species from Britain and Ireland, to learn their evolutionary relationships.

This project also contributes to the much larger, Earth BioGenome Project.

One of the teams taking part in this project, based at the Wellcome Sanger Institute and the University of Edinburgh, Scotland, has just completed the sequencing of 200 high-quality genome of the Lepidoptera order of insects (moths and butterflies) and discovered some interesting facts about the evolution of the order, including that there are some elements in the genomes, which they term 'Merian elements' after the 17th century entomologist Maria Sibylla Merian, which have remained relatively stable over the 250 million years the order has been evolving.

The research is published in the journal Nature Ecology & Evolution and is described in a Welcome Sanger Institute news release:

Monday 29 January 2024

Creationism in Crisis - The Billion-Year Evolutionary History of Plants On Earth


Since the first plants appeared, they have diversified into a vast range of forms, and sizes from pond scum to massive trees.

How did plants first evolve into all different shapes and sizes? We mapped a billion years of plant history to find out

Plants come in all manner of shapes and sizes, varying in complexity from simple single-celled algae, through mosses, liverworts and ferns to flowering plants and massive trees.

But how did they get this way?

A team of scientists led by Philip C J Donoghue, Professor of Palaeobiology, University of Bristol, James Clark, Research Associate, School of Biological Sciences, University of Bristol and Sandy Hetherington, Plant Evolutionary Biologist, The University of Edinburgh, set out to answer this question by looking at certain traits in each major plant group. The traits ranged from fundamentals like the presence of roots, leaves or flowers to the fine details such as the surface topography of pollen grains. All in all, the team collected data on 548 traits from more than 400 living and fossil plants, amounting to more than 130,000 individual observations.

They then used this data to plot the positions of plants, living and extinct in a 'design space', i.e., the theoretical range of possible forms for each major group.

What they found was that there tended to be a burst of diversification soon after the evolution of a major new trait, with the new lineage then tending to settle down to improve on what they had, rather than to innovate - until the next major innovation.

This what we would expect from the way a major new trait, such as the evolution of pollen as the male reproductive cell which could be transferred to the female by wind, insects, etc., so freeing the plants from the need to live in water or damp conditions so the motile male cells could 'swim' to the female, as it still does with the gametophytes - mosses, liverworts and ferns.

This innovation meant plants were not free to diversify into the dryer land between rivers, lakes and coastal margins and so colonise much more of the planet.

The same phenomenon is seen in animals where, for example, terrestrial living freed the early amphibians from dependence on water, except to breed, and the evolution of eggs, freed them even from that dependence; the evolution of flight freed the birds and bats to diversify into the new niches now open to them.

The team's work was published, open access in Nature Plants and is the subject of an article in The Conversation by the three lead authors. Their article is reprinted here under a Creative |Commons license, reformatted for stylistic consistency:

Saturday 9 December 2023

Unintelligent Design - The Late Devonian Mass-Extinction Or How Earth Is Badly Designed For Life


Fieldwork at Trail Island in East Greenland, near a Late Devonian rock outcrop.
Photo by John Marshall, University of Southampton
Study reshapes understanding of mass extinction in Late Devonian era: IU News

Way back 370 million years before the mythical 'Creation Week' the seas were full of life and angiosperm plants were rapidly replacing the tree ferns and other Tracheophytes and life was looking good, despite the fact that the single large landmass, Pangea, was on the point of breaking up.

Then something happened to cause another of those periodic mass extinctions that have punctuated Earth's long 'pre-Creation' history. What exactly it was has been the subject of ongoing debate by geologists, biologists and climatologists ever since evidence of it was found in the fossil record, particularly in Devonian rocks like those in Greenland.

But whatever the cause, it's not good news for creationists who have been duped by their cult leaders into believing Earth is fine-tuned for life by a designer god, and, by the circular reasoning that characterises creationism, therefore this fine-tuning 'proves' their designer god exists. A cynic might wonder, if faith is any good, why creationists are so desperate to find scientific 'proof' of their god that they perform all manner of ludicrous mental gymnastics and commit just about every logical fallacy in the book, to tell themselves and their target dupes that they have discovered it - and will be producing it any day now, real soon!

But that's by the by.

Sadly for creationists the evidence is that Earth is anything but finely tuned and perfect for life. The simple truth is that an Earth that was perfectly designed for life would never have extinctions, let alone mass extinctions like the ones that ended the Devonian and Cretaceous eras, and the one that's in progress right now. In fact, there would not even be biodiversity on such a planet because there would be no reason to adapt to adverse conditions because since these would not exist on a perfectly designed Earth, so life would not have progressed beyond the simplest of self-replicating molecules.

So, just for any creationists still under the delusion that Earth is finely tuned for life, here is a brief description of the Devonian and the mass extinction at the end of it:

Monday 4 December 2023

Wonderful World - Ten Reasons to Like Spiders


Female house spider, Tegenaria domestica
Don't like spiders? Here are 10 reasons to change your mind

Back in the past, in what now seems like a lifetime ago, I managed the Emergency Operations Centre for my local Ambulance Service which was housed in a single-storey building in the grounds of the Church Hospital, Oxford. One of my nicknames was 'Spiderman' because of my fondness for spiders.

The roof space of this building was home to a population of 'house spider' or Tegenaria domestica, a good-sized one of which can be 4 inches or more across its outstretched legs. They frequently paid us a visit by coming through the light fittings or round the edges of the aircon unit.

The house spider is well-named, being one of those commensal species that, like barn swallows, can't exist without human habitation and so must have evolved after we became settled and built permanent dwellings.

Despite its large fangs, it is entirely harmless to humans, even if it does manage to pierce the skin - something I tried to impress on my staff, whose first response to one running across the floor was to stamp on it.

Despite this reassurance, one of my assistants was so arachnophobic she refused to enter the room until the spider was gone - although what she thought it would do to her was a mystery, so one of my tasks was to gently catch the spider in my hands and put it outside, whereupon I would deliver my famous (or maybe infamous) spider talk, in which I explained why spiders are such fascinating creatures - their very long evolutionary history from a common ancestor with scorpions; their multiple eyes (some for binocular vision and some for detecting movement) and above all their amazingly engineered webs.

Orb web spiders like the common garden spider, Araneus diadematus, make two sorts of silk - one to act as scaffolding and the radial threads of the web and sticky one to form the circular strands. Each thread of silk consists of multiple fine filaments that stretch very quickly to catch a flying insect without it bouncing off, then recoil slowly to avoid throwing the insect free. All this is controlled by the fine molecular structure and electrostatic bonds between the filaments. The result is a thread that, weight for weight, is stronger than steel.

One small spider that is common on walls and buildings in Oxford is the zebra spider, Salticus scenicus, a tiny black and white-striped spider, only a few millimeters long, that has amazing eyes. It is a hunting spider that preys on small insects, even some three times its size, by jumping on them. Its modus operandum is to crawl over the surface of walls and roofs and, when it sees its prey, it approaches slowly and when close enough, judges the distance perfectly and pounces. It will also jump across gaps, again with a perfectly judged jump, many times its own body length, rather like a human jumping the Grand Canyon from a standing start, but before it does so, it dabs the tip of its abdomen down to fix a 'safety line' of silk, just in case. To perform these feats, the zebra spider needs a high degree of visual acuity and binocular vison. The amazing thing about this spider is the way it overcomes the problem for visual acuity of such a small retina; it rapidly moves the retina up and down, effectively increasing its size.

The jump is accomplished, not by muscles in the legs, but by a sudden increase in haemocoelic blood pressure which straightens the front and back legs, so the spider always jumps with its legs extended.
I always hoped my spider talk would impress my staff enough to take an interest in spiders rather than seeing them as creepy-crawly things to be half-feared and killed simply for sharing the building with us. Alas, only one or two ever followed my example and picked them up to put them out of a window.

All that was by way of introduction to an article in The Conversation in which Leanda Denise Mason, an Associate Lecturer, Curtin University, Australia give her ten reasons to like spiders, or at least change your mind it you don't. Her article is reprinted here under a Creative Commons licence, reformatted for stylistic consistency. The original can be read here.

Sunday 3 December 2023

Creationism in Crisis - Scientists Show How a Dynamic And Changing Earth Influenced Evolution Over Millions of 'Pre-Creation' Years


Landscape dynamics determine the evolution of biodiversity on Earth - The University of Sydney
A dynamic and changing Earth.
Again, it's the turn of geologists to refute creationism without even trying, like so many biologists do with their daily work.

Creationists insist that Earth is 'fine-tuned' for life; but as anyone who understands biology will know, life is 'fine-tuned' for Earth and the tuning process is called evolution by natural selection.

The observable fact that, over time, species have either evolved or gone extinct gives the lie to the 'fine-tuned for life' assertion because, if that were true, there would be no selection pressure for change and the fossil record would show no change.

In fact, the fossil record wouldn't exist as we know it because there would have been no evolution beyond the first free-living, single-celled prokaryote organisms because their environment would have been perfect for them.

Yet, as we know from daily observation, Earth is a changing and dynamic planet with periodic climate change, earthquakes and volcanoes caused by the slow process of plate tectonics, changing oxygen and carbon dioxide levels caused by the rise and fall of major ecosystems, and changing ocean currents caused by a number of different factors, not the least of which are climate change and plate tectonics. Then there are the cosmological changes caused by the Milankovitch cycles.

One of the consequences of this dynamic change is the way the Earth's surface is continually being recycled over geological time by erosion, transportation in water and sedimentation in ocean deposits as nutrients, then subduction and mountain-building and eventual resurfacing through volcanic activity. This gives changing levels of nutrients in the oceans that affect biodiversity both in the seas and on land.

This is the conclusion of a study by a team of geologists jointly led by Dr Tristan Salles of The University of Sydney, Sydney, New South Wales, Australia, and Dr Laurent Husson of Université Grenoble-Alpes, Grenoble, France. They have shown an association between changes in nutrient levels due to sedimentation and mass extinctions. Their findings are published open access in Nature and are explained in a University of Sydney news release:

Saturday 2 December 2023

Creationism in Crisis - How Snakes Evolved To Meet The Demands Of Their Habitat And Food Sources


Dipsas catesbyi, a snail-eating species
Snake skulls show how species adapt to prey - News Center - The University of Texas at Arlington

The ability to catch and consume prey species is a key aspect of evolutionary biology in carnivorous species, for obvious reasons, and so is a major source of divergence and radiation of species as each species become more and more specialised at catching different prey species.

An example of this was published recently in the journal BMC Ecology and Evolution in which three researcher, led by Gregory G. Pandelis of the Amphibian and Reptile Diversity Research Center, Department of Biology, University of Texas at Arlington, Arlington, Texas, USA with two colleagues from the Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA, showed a correlation between prey species and skull morphology in dipsadine snakes.

Saturday 11 November 2023

Creationism in Crisis - An Ancient 'Transitional' Species Rediscovered - An Egg-Laying Mammal


Attenborough's long-beaked echidna, Zaglossus attenboroughi
Found at last: bizarre, egg-laying mammal finally rediscovered after 60 years | University of Oxford

Creationists are always clamouring for evidence of 'transitional' species or fossils, only to dismiss them as 'fully-formed species' so 'not transitional'. What they're demanding is that we show them something that no biologist ever claimed existed - a fossil of something that was half one species and half another - a croccoduck or a half human-half chimpanzee fossil, in other words evidence of their childish parody of evolution.

Instead, what we have is countless examples of species with archaic features and stem species showing characteristics of more primitive taxons and later species that would evolve from it. In fact, every fossil ever found is 'transitional' between its parent generation and its descendant population - a fact only understandable by those with a grasp of what evolution is and how it works over time.

And one such group of animals showing archaic features that show the transition from egg-laying reptiles and the mammals that evolved from them are the monotremes, egg-laying mammals such as the platypus and echidnas - vertebrates that are warm-blooded, have fur and feed their young on milk secreted by special glands on the female's body.

Wednesday 25 October 2023

Creationism in Crisis - Research Shows How Environment Drives Evolution - No Magic Required


Raining Cats and Dogs: Research Finds Global Precipitation Patterns a Driver for Animal Diversity

A team of researcher from Utah University's Department of Watershed Sciences in Quinney College of Natural Resources and the Ecology Center, led by Jaron Adkins, has investigated why there is a rich diversity of species in some areas and a paucity of species in others. Not surprisingly, given what we know of how diversity evolves due to environmental selectors, they found a close link between diversity and the environment, especially rainfall, and the result of rainfall, or a lack of it - plant growth.

Monday 23 October 2023

Creationism in Crisis - Disastrous Sea Level And Climate Changes - 385 Million Years Ago.


2023-10 - Ancient sea level and climate changes led to major extinctions around South Africa - Wits University

A planet designed by a loving, omniscient designer would be stable and not subject to periodic bouts of mass extinction because the life on it couldn't cope with a massive environmental change.

And yet new research by Dr Cameron Penn-Clarke from the University of the Witwatersrand and Professor David Harper from Durham University has shown that a catastrophic environmental change in the Early Devonian caused the mass extinction of the Malvinoxhosan biota. This was in the 99.97% of Earth's history that occurred before the Universe was created out of nothing by magic, according to creationists.

The term 'Malvinoxhosan biota' foxed ChatGPT3.5:

Sunday 22 October 2023

Creationism in Crisis - Why Earth is Fine Tuned for Extinction


September: Nature Geoscience extreme heat | News and features | University of Bristol

Creationists like to imagine that Earth is fine-tuned for life. This belief depends on the parochial ignorance of the creationist of course, because they will be oblivious of the fact that, cozy though their small bit of the planet might be, most of it is uninhabitable by humans without specialist equipment, and even cloths and houses are required in the temperate areas. Human life would be impossible without modern technology in the oceans, deserts, arctic waste, the tops of high mountains or just a few thousand feet above the surface of the planet (this is why modern aircraft that fly at 30-60,000 feet need to be pressurised).

But a planet that is fine-tuned for life would also have an infinite life-span, not a time-limited one where the life-time is limited by entirely natural processes, such as plate tectonics and the solar cycle. In fact, the life span of Earth is a mere blink on a cosmic time-scale that is measured by the life of suns.

Long before the sun becomes a red giant and swallows up the inner planets at the end of its life, shortly before becoming a super nova and blowing away the outer planets, Earth's continents will have coalesced into another single super-continent, reminiscent of Pangea, and the climate will have made life untenable for most species of mammal, according to researcher at Bristol University.

The resulting increase in volcanic rifting and out-gassing, combined with 'continentality' and an increase in solar energy output, will result in a 'wet-bulb' temperature of >35oC and a 'dry bulb' temperature of >40oC - temperatures at which mammalian thermoregulation fails, leading to death in about 6 hours.

The team's findings are published open access in Nature Geoscience and explained in a Bristol University press release:

Thursday 19 October 2023

Creationism in Crisis - Scientists Have Shown How Mosquitoes Evolved in Another Casual Refutation of Creationism With Facts


Aedes eagypti
Anopheles stephensi
Anopheles albimanus
Ochlerotatus notoscriptus
Study Elucidates Evolution of Mosquitoes and Their Hosts | NC State News

It's proving to be another terrible week for the creation cult with yet another science paper that casually, and without any intention on the part of the authors, utterly refutes some basic creationist cult dogmas.

This paper deal with the evolution of the mosquitoes and the parasite-host relationship that refute intelligent design ideas with their arms races, needless complexity and prolific waste, in addition to their refutation of the notion of an omnibenevolent designer.

And of course, as we've come to expect, almost all that evolutionary history occurred millions of years before creationists think the Universe was magically created out of nothing by a magic man made of nothing who popped up from nowhere, in the days when nothing was something that existed. This magic, invisible man then allegedly created every living thing without ancestors, pretty much as we find it today, but on a flat Earth with a dome over it to keep the water above the sky out. Seriously!

The point has already been made by others many times before: creationism is not a problem for science; science is a problem for creationism; and this paper is just one more drop in the tsunami engulfing the cult.

First, a little AI background on mosquitoes:

Wednesday 27 September 2023

Creationism in Crisis - Complexity May be an Accidental Consequence of Evolution, Not its Inevitable Result.



It's reassuring to think humans are evolution's ultimate destination – but research shows we may be an accident

In the creationist parodies of the Theory of Evolution, evolution is presented as a theory that organisms become more and more complex and at the apex of evolution are human beings, the most complex of all species.

Of course, the real TOE says no such thing and claims about aims and purpose, with humans as the intended outcome, are childishly anthropocentric in the extreme. Nor is complexity the inevitable result of evolution since many species, especially parasites, have evolved with a loss of complexity and genetic information. But in general, ignoring parasites, much of evolution does include an increase in complexity, though not always an increase in genetic information. Many salamanders, such as the axolotl, have a much larger genome than humans and even the Christmas tree has a genome 7 times larger than the human genome.

The most complex organism, genetically speaking, is in fact a relatively simple, single-celled amoeba, Amoeba dubia, with a genome 60 times larger than the human genome.

Tuesday 22 August 2023

Creationism in Crisis - Urban Great Tits Have Beome Paler Than Their Rural Relatives


European great tit, Parus major.
Urban great tits have paler plumage than their forest-living relatives | Lund University

In an example of how the environment, and in this case probably the availability of different food items, can cause changes on which natural selection can act, a study by an international team or reserchers led by Pablo Salmón of Lund University, Sweden, has shown that great tits, Parus major living in an urban environment have paler breasts than those living in a forest environment.

Although this is probably not an evolutionary change, i.e., a change in the frequency of alleles in the population gene pools, as the cause is probably dietary difference, it illustrates how an environmental change can produce changes in features on which natural selection can act to bring about true evolutionary changes, and so begin the process of allopatric speciation.

Of course, there will be creationists who will misrepresent the scientific fact of evolution, either deliberately, or mendaciously in order to mislead others, who will dismiss this as "not evolution", not for the reason given above but because "they're still great tits/still birds" and haven't grown a new structure or turned into an unrelated taxon.

The research is explained in a Lund University press release:

Wednesday 19 July 2023

Creationism in Crisis - Genes for Learning, Memory and Complex Behaviour Evolved 650 Million years Ago!


Examples of bilaterians each with genes first evolved in the pre-Cambrian.
Genes for learning and memory are 650 million years old, study shows | News | University of Leicester

Bilaterians are a group of animals characterized by bilateral symmetry, which means they have a left and right side that are mirror images of each other. This symmetry allows for a clear front and back end, as well as distinct top and bottom surfaces. Bilaterians are among the most diverse and successful animal groups on Earth.

The emergence of bilaterians marked a significant milestone in the evolution of life. They evolved during the Cambrian explosion, a period around 541 million years ago when there was a rapid diversification of complex animal life in the fossil record.

Bilaterians gave rise to a wide array of animal lineages, many of which are still present today. Some of the major groups that evolved from bilaterians include:
  1. Deuterostomes: One of the major branches of bilaterians, deuterostomes include several important animal groups, such as vertebrates (fish, amphibians, reptiles, birds, and mammals) and echinoderms (starfish, sea urchins, and sea cucumbers).
  2. Protostomes: Another major branch of bilaterians, protostomes include diverse groups such as arthropods (insects, spiders, crustaceans), mollusks (snails, clams, squids), annelids (earthworms, leeches), and many others.
Bilaterians were crucial in shaping the animal kingdom and played a pivotal role in the complex ecological relationships that emerged throughout Earth's history. They eventually diversified into the incredible variety of animal species that we see today.

ChatGPT3 "What were bilaterians and what did they evolve into?" [Response to user question]
Retrieved from https://chat.openai.com
Imagine, you're a creationist fool whose cult leaders have made to feel smugly self-important because a supernatural magic man created your ancestors specially with uniquely humans abilities that set you apart from the other animals, just a few thousand years ago, like the ability to learn, remember and have complex social interactions.

Then along comes a bunch of those spoil-sport scientists who shows that the genes for those things evolved in some very primitive ancestors, the bilaterians, 650 million years ago and so are shared with all the multitude of descendants of those primitive organisms.

How do you handle this new information while still feeling the smugly self-important special creation of the creator of the universe?

You can't allow yourself to think you could be wrong, because that would spoil the whole delusion, so you ignore the science, abuse the scientists, or simply declare it all wrong, and carry on believing the myth of your special importance.

But the problem is the research findings are still there and won't go away just because you've ignored them or declared them wrong, so, whatever you do, avoid reading what follows because it is from a press release from the university of Leicester, UK, where the leaders of the research team were from, and the open access paper in Nature Communications where they published their findings:

Saturday 20 May 2023

Creationism in Crisis - How a 'Macro-Evolutionary' Change can be Produced by Changes to a Few Genes

Creationism in Crisis

How a 'Macro-Evolutionary' Change can be Produced by Changes to a Few Genes.
A transient change in expression of one gene (Shh) can produce a cascade of developmental events leading to the formation of feathers instead of scales


© UNIGE / Cooper & Milinkovitch
Sablepoot batams
Sablepoot bantams
Scales or feathers? It all comes down to a few genes - Medias - UNIGE

Lurk a while in any Evolution vs Creationism group in the social media and you can guarantee a creationist will try to argue that a given example of evolution which they have probably just deamnded be provided, and which conforms to the scientific definition of evolution - any change in allele frequency over time - is not real evolution because it wasn't 'macro-evolution' which they will define as a change in 'kind' or the evolution of a new species, even the evolution of new structures - whichever definition they think stands the best chance of winning.

I've been at this for long enough to remember how, when the early internet 'bulletin boards' on CompuServe had morphed into thriving debate 'forums', creationists would simply argue that there was no such thing as evolution, full stop! It simply never happened; not in the slightest. No Way! Everything was created exactly as it is today during 'Creation Week' a few thousand years ago! Any evidence to the contrary was a forgery by evil scientists or had been planted by Satan.

Then, in the face of so much evidence, particularly the very large number of living and extinct species and the impossibility of them all being collected together in a few days, herded onto a wooden boat and surviving for a year, they began to concede that there had indeed been evolution, but only limited to evolution withing species, and evolution moreover at a phenomenal rate, far exceeding anthing proposed by biologists, so as to produce the millions of species from a few 'kinds' that survived the genocidal flood their putative creator had inflicted on its creation, just a few thousand years ago.

What creationists are doing is moving the goal-posts by redefining a well-understood scientific term to place it beyond what science actually claims, so they can demand evidence of something that no evolutionary biologist ever claimed - that a single mutation produced a new species or that one species gave birth to another in a single event, ignoring the fact that evolutionary biologists understand the evolution is normally a slow process which takes place in the species gene pool, with the instances of new species arising by, for example, hybridization, being rare exceptions, but nevertheless, natural processes, not requiring supernatural entities to explain.

So, ask a creationist now wedded to the notion that real evolution needs to be 'macro-evolution' to define a reptile 'kind' and a bird 'kind' and they will normally define a reptile 'kind' as having scales and a bird 'kind' as having feathers, ignoring the fact that paleontologists have discovered several feathered dinosaurs (reptiles).

Now, present a creationist with an example such as the one in this research paper, where changes to a small number of genes resulted in what they would define as 'macro-evolution', i.e., a change in 'kind' because that change in chickens results in them growing feathers where they normally grow scales, showing the feathers are simply evolved scales.

Evolution in Action - Giant Spiders Spreading Across Southern USA

Slideshow code developed in collaboration with ChatGPT3 at https://chat.openai.com/

The Jorō spider, Trichonephila clavata
Joro spiders aren’t scary. They’re shy.

A rather beautiful large spider is rapidly spreading across the southern USA, aided by a couple of attributes that enable it to adapt to human habitation, in a stunning example of how the environment can select for species fitted to live and thrive in it. A related species, T. clavipes, has already established itself in southern USA.

The spider, Trichonephila clavata, is a very large, but harmless (to humans), Jorō spider, the subject of a recent research paper in the journal Arthropoda. The research, carried out by researchers, by Andrew K. Davis and Amitesh V. Anerao of Odum School of Ecology, University of Georgia, Athens, GA, USA.

The study shows that, in a classic example of how particular traits can enable a species to extend its range, T. clavata is good at living alongside humans. Rather than being aggressive, which most people would assume is the reason it is out-competing native American spiders, T. clavate is particularly shy and non-aggressive. Despite their size and warning colouration, they are harmless to humans and pets. They will only attempt to bite if picked up and trapped and even then, their fangs aren't large enough to pierce human skin.

Interestingly, their avoidance strategy is to remain completely motionless for about an hour when disturbed, unlike most spiders which normally resume activity after few minutes, leading the researchers to classify them as 'shy' rather than aggressive.

The research is explained in a University of Georgia press release:
New study suggests the massive spiders are gentle giants, mean people no harm

One of the ways that people think this spider could be affecting other species is that it’s aggressive and out-competing all the other native spiders, so we wanted to get to know the personality of these spiders and see if they’re capable of being that aggressive. It turns out they’re not.

They basically shut down and wait for the disturbance to go away. Our paper shows that these spiders are really more afraid of you than the reverse.

One thing this paper tells me is that the Joros’ rapid spread must be because of their incredible reproductive potential,” Davis said. “They’re simply outbreeding everybody else. It’s not because they’re displacing native spiders or kicking them out of their own webs.

Dr. Andrew Davis, lead author Odum School of Ecology, University of Georgia, Athens, GA, USA.
Despite their intimidating appearance, the giant yellow and blue-black spiders spreading across the Southeastern U.S. owe their survival to a surprising trait: They’re rather timid.

According to a new study from the University of Georgia, the Jorō (Joro) spider may be the shyest spider ever documented.

The researchers compared more than 450 spiders’ responses to a brief and harmless disturbance across 10 different species.

While most spiders froze for less than a minute before resuming their normal activities, the Joro spiders remained motionless for more than an hour.

In fact, Joros are relatively harmless to people and pets. Joros won’t bite unless cornered. And even if you did manage to somehow annoy a Joro into biting you, its fangs likely wouldn’t be large enough to pierce your skin.
A female Joro spider spins its web. The 30mm scale bar is included for size reference.

Credit: Jeremy Howell

Most spiders begin moving quickly after stress, Joros remain immobile for 60-plus minutes

To examine the spiders’ reaction to stress, the researchers used a turkey baster to gently blow two rapid puffs of air onto individual spiders. This minor disturbance causes the spiders to “freeze” for a period of time, going absolutely still.

The researchers tested more than 30 garden spiders, banded garden spiders and marbled orb weavers. They also analyzed similar data from previously published, peer-reviewed papers that assessed the response of 389 more spiders, comprising five additional species.

All of those spiders began moving again after an average of about a minute and half of stillness.

The Joros, however, stayed frozen with no body or leg movement for over an hour in most cases.

The only other spider species that exhibited a similarly extended response was the Joro spider’s cousin, the golden silk spider. Known as Trichonephila clavipes, the golden silk spider and the Joro spider are from the same genus.
A Joro spider feasts on a caterpillar.

Joros may be invasive, but they’re not aggressive

Most people think ‘invasive’ and ‘aggressive’ are synonymous. People were freaking out about the Joro spiders at first, but maybe this paper can help calm people down.

They’re so good at living with humans that they’re probably not going away anytime soon.

Amitesh Anerao, co-author of the study,
Undergraduate researcher, Georgia University, Athens, GA, USA
Officially known as Trichonephila clavata, the East Asian Joro spider first arrived in Georgia around 2013. The species is native to Japan, Korea, Taiwan and China, and likely hitched a ride stateside on a shipping container.

The species has since rapidly spread across the state and much of the Southeast. Joro spiders easily number in the millions now. And there’s not much we can do to stop them from increasing their range.

Davis’ previous research even suggested the invasive arachnids could spread beyond their current habitats and through most of the Eastern Seaboard.

Sunlight streams through the elaborate webs made by Joro spiders
Joro spiders built to withstand human activity

Joros are regularly spotted in areas native Georgia spiders don’t typically inhabit.

They build their golden webs between powerlines, on top of stoplights and even above the pumps at local gas stations—none of which are particularly peaceful spots.

The researchers believe the Joro spiders’ shyness may help them better endure the barrage of noise, vibrations and visual stimuli they consistently encounter in urban settings. Their prolonged freeze response to being startled could help conserve the Joro spiders’ energy.

If you’re wondering how something so mild-mannered could spread the way Joro spiders have, you aren’t the only one.

Arachnophobes can take solace in the Joro spiders’ meek and gentle temperament. But the spiders are likely here to stay.
Bar chart of results
Figure 2. Behavioral responses of spiders to a mild disturbance stimulus (air puff), from our tests, plus from data presented in published studies (see Table 1). Shown are the mean durations of time spent in a “thanatosis” state after receiving the stimulus.

Copyright: © 2023 The authors.
Published by MDPI (Basel, Switzerland). Open access. (CC BY 4.0)
The researcher’s paper is available, open access, in the journal,Arthropoda:
Abstract

The jorō spider (Trichonephila clavata, originally from east Asia) has been introduced in the southeastern United States, and is rapidly expanding this range, leading to questions about what facilitates this spread. Meanwhile, its cousin, the golden silk spider (T. clavipes), already has a range that covers most of the southeast. In an ongoing effort to understand the behavior of jorō spiders in their introduced range, we undertook the current project to evaluate how they react to perceived threats, which can inform us on how a species interacts with conspecifics, or how well it can tolerate anthropogenic disturbances. We collected mature females of both Trichonephila species, plus three locally common orb-weaving species in Georgia, and we evaluated the time spent immobile after experiencing a mild disturbance (a brief puff of air). We also collected similar “air puff response” data for five other North American species from the published literature. Collectively, the dataset totaled 453 observations of freezing behavior across 10 spider species. Comparing these data across species revealed that most spiders remained immobile for under a minute after the stimulus. Meanwhile, both Trichonephila spiders remained immobile for over an hour, which appears to be unprecedented, and suggests that spiders in this genus are the “shyest” ever documented. This reaction could also allow Trichonephila spiders to tolerate urban environments by remaining motionless throughout each disturbance instead of fleeing.

A classic study showing how traits can facilitate the spread of a species into new territories provided the local environment provides the right selectors, if not, of course, introduction won't succeed. And once again confirming the relationship between a species and its environment and how the latter selects for traits which produce more copies than other alleles.

All perfectly understandable in terms of natural processes, with not a hint that supernatural magic had to be involved at some point.

And yet creationism is still managing to recruit new scientifically illiterate fools into the cult, despite all its counter-factual claims and readily available evidence refuting them.

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Thursday 18 May 2023

Creationism in Crisis - Researchers Have Worked Out How Butterflies Evolved

Slideshow code developed in collaboration with ChatGPT3 at https://chat.openai.com/

Blue morpho butterfly
Blue morpho butterfly, Morpho peleides

Kristen Grace/Florida Museum
Butterfly tree of life reveals an origin in North America – Research News

Butterflies first began to diverge from moths about 100 million years ago. It had been assumed that this was to avoid nocturnal bats by flying during the day, but a group of geneticists led by Akito Y. Kawahara, of the McGuire Center for Lepidoptera and Biodiversity in the Florida Museum of Natural History, FL, USA, have now shown that a diurnal existence was made possible by the evolving relationship between flowering plants and bees, which provided an energy-rich source of nectar.

By analysising the DNA from more than 2,000 species representing all butterfly families and 92% of genera, the world-wide team of scientists have traced the movements and feeding habits of butterflies through time in a four-dimensional puzzle that led back to North and Central America. Their results were published, open access, a couple of days ago, in the journal Nature, Ecology & Evolution.

As the Florida Museum news release explains:
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