F Rosa Rubicondior

Monday 20 May 2024

Creationism in Crisis - How An Extinct Duck Got To New Zealand In The Millions Of Years Before 'Creation Week'


Auckland Island merganser specimen

Ancient DNA from an extinct native duck reveals how far birds flew to make New Zealand home

Ducks, like almost all taxonomic categories, are a nightmare for creationists because they aren't mentioned in the Bible so it's not possible to put them into their primitive 'kind' classification, other than saying they are some 'kind' of bird, or maybe a 'duck kind'. The problem is there are so many different families of duck and several different species within each family. Some of them look very different to other ducks and have clearly evolved unique characteristics such as the long, serrated beak of the fish-eating mergansers, which places them in a different clade to the dabbling diving and torrent ducks.

By any definition then, evolving from a basic 'duck' into a merganser is the evolution of a new taxon, or 'macro-evolution' as creationists like to call it, while proclaiming it to be impossible because of some undefined magical process that intervenes to prevent it.

Which leaves creationists with nowhere to go but to claim mergansers were on the Ark, since they couldn't have evolved from a parent pair of 'ducks' at the abnormal warp-speed rate of evolution, that no-one noticed or thought to record, that creationists now claim must have happened in the few years since their favourite genocidal flood, that left no trace of itself.

But that's nothing compared to the genetic evidence that shows how, for example, the mergansers, evolved and spread geographically 18 million years before creationists believe there was a universe and again between 14 and 7 million years before creationists' god decided to create a small flat planet with a dome over it in the Middle East, 10,000 years ago, that creationists still believe accurately describes all that there is.

First, a little AI information about mergansers:
Tell me all about mergansers, their distribution and evolutionary origins, please. Mergansers are a group of ducks belonging to the genus Mergus, which is part of the family Anatidae. They are known for their distinctive serrated bills, which are well-adapted for catching fish, their primary diet. Here’s a detailed overview of mergansers, including their distribution, characteristics, and evolutionary background.

Characteristics Mergansers are medium to large-sized ducks with slender bodies and long, pointed bills. Their bills are equipped with saw-like edges that help them grasp slippery fish. There are several species within the Mergus genus, including:
  1. Common Merganser (Mergus merganser): Also known as the goosander, this species has a widespread distribution across North America, Europe, and Asia.
  2. Red-breasted Merganser (Mergus serrator): Found in North America, Europe, and Asia, this species prefers coastal and large inland waters.
  3. Hooded Merganser (Lophodytes cucullatus): Native to North America, it is smaller than other mergansers and has a distinctive fan-shaped crest.
  4. Brazilian Merganser (Mergus octosetaceus): One of the rarest mergansers, it is found in central Brazil and is critically endangered.
  5. Scaly-sided Merganser (Mergus squamatus): This species inhabits parts of East Asia and is also considered endangered.

Distribution

Mergansers have a wide distribution, with different species occupying various regions around the globe:
  • Common Merganser: Breeds in forested regions near lakes and rivers across northern North America, Europe, and Asia. In winter, they migrate to more temperate areas.
  • Red-breasted Merganser: Found in boreal and temperate regions across the Northern Hemisphere. They often winter in coastal waters, estuaries, and large inland lakes.
  • Hooded Merganser: Prefers forested wetlands, rivers, and ponds in North America. They are non-migratory in some parts of their range but move to ice-free waters in winter.
  • Brazilian Merganser: Restricted to central Brazil, particularly in the Serra da Canastra region. Their habitat includes clear, fast-flowing rivers.
  • Scaly-sided Merganser: Breeds in forested rivers of northeast China and the Russian Far East. They migrate to southern China, Korea, and Japan for winter.

Evolution

Mergansers belong to the Anatidae family, which includes ducks, geese, and swans. The evolution of mergansers is part of the broader adaptive radiation of the Anatidae, which diversified to exploit a variety of ecological niches. The serrated bills of mergansers are a specialized adaptation for piscivory (fish-eating), differentiating them from other ducks.

Evolutionary Background
  1. Ancestral Origins: The Anatidae family likely originated in the late Cretaceous to early Paleogene periods. Early diversification allowed these birds to adapt to various ecological roles, including herbivory, omnivory, and piscivory.
  2. Adaptive Radiation: The diversification of Mergus species is an example of adaptive radiation, where different species evolved to occupy different ecological niches, particularly in terms of habitat preference and diet specialization.
  3. Morphological Adaptations: The distinctive serrated bills of mergansers are a key evolutionary trait that sets them apart from other ducks. This adaptation is crucial for their fish-based diet.

Conservation Status

Several species of mergansers are of conservation concern:
  • Brazilian Merganser: Critically endangered, with an estimated population of fewer than 250 individuals in the wild. Habitat destruction and water pollution are major threats.
  • Scaly-sided Merganser: Endangered, with threats including habitat loss due to logging and river damming, as well as pollution and human disturbance.

Conclusion

Mergansers are a fascinating group of ducks with specialized adaptations that enable them to thrive as piscivores in a variety of aquatic habitats. Their wide distribution and evolutionary history reflect the dynamic processes of diversification and adaptation in the Anatidae family. Conservation efforts are crucial for the survival of the endangered species within this group, highlighting the need for habitat protection and restoration.

The evidence of when the now extinct New Zealand merganser got to New Zealand and how it is related to other mergansers is the subject of an article in The Conversation by Nic Rawlence, Senior Lecturer in Ancient DNA, and Alexander Verry, Researcher, both of the University of Otago, New Zealand. Their article is reprinted here under a Creative Commons license, reformatted for stylistic consistency:


Ancient DNA from an extinct native duck reveals how far birds flew to make New Zealand home
Auckland Island merganser. Artistic reconstruction by J. G. Keulemans from Bullers Birds of New Zealand (1888)
Bullers Birds of New Zealand, Author provided
Nic Rawlence, University of Otago and Alexander Verry, University of Otago

Ask a bird lover if they have heard of the extinct giant moa or its ancient predator, Haast’s eagle, and the answer will likely be yes. The same can’t be said of New Zealand’s extinct, but equally unique, mergansers – a group of fish-eating ducks with a serrated bill.

The only southern hemisphere representatives of this group are the critically endangered Brazilian merganser and those from the New Zealand region, which are now extinct.

Unlike some of New Zealand’s other extinct birds, the biological heritage of our enigmatic mergansers is shrouded in mystery. But our new research on the extinct Auckland Island merganser is changing the way we think about the origins of New Zealand’s birds. Did the ancestors of the merganser come from South America or the northern hemisphere – and when did they arrive?
Map of merganser distribution
Mergansers are relatively common in the northern hemisphere but were limited to Brazil and the New Zealand region in the southern hemisphere.
Author provided
Lost to humans and pests

Mergansers were spread across the three main islands of New Zealand at the time of Polynesian arrival in the 13th century, as well as the Auckland Islands to the south and the Chatham Islands to the east.

Over-hunting, habitat destruction, and predation from the Pacific rat and Polynesian dog resulted in the extinction of mergansers on the New Zealand mainland and the Chatham Islands. By the time Europeans arrived in the 17th century, mergansers were restricted to an isolated population on the sub-Antarctic Auckland Islands.

European discovery of the Auckland Islands in 1806 led to a formal description of the Auckland Island merganser in 1841. However, European discovery brought new predators like pigs and cats.

Mergansers were also sought after as specimens for the museum trade. The last known Auckland Island merganser was shot and collected in 1902, a mere 61 years after its discovery.
A museum example of the Auckland Island Merganser
Auckland Island Merganser, Mergus australis, collected June 1902, Auckland Islands, New Zealand.

Only recently have merganser bones from the Chatham Islands been described as a distinct species. The distinction of the Chatham Island merganser hints at greater merganser diversity in the New Zealand region than previously thought. It is possible the merganser bones found on mainland New Zealand may be another species, but only ongoing research will be able to confirm this.

From the northern hemisphere to NZ

The extinction of mergansers from the New Zealand region has meant their evolutionary history has remained a mystery. Did their ancestors, and those of the Brazilian merganser, arrive via independent colonisation events from the northern hemisphere? Or was there a single push into the southern hemisphere, followed by subsequent divergence events?

To find out more, we sequenced ancient DNA from an Auckland Islands merganser and a Brazilian merganser. This allowed us to reconstruct the evolutionary history of the wider group.

We found mergansers originated in the northern hemisphere, diverging from their closest relatives some 18 million years ago, before rapidly evolving into several different species between 14 and seven million years ago.

The mergansers from the New Zealand region are most closely related to the northern hemisphere common merganser. Their ancestors arrived here at least seven million years ago in a separate colonisation event to the one that gave rise to the Brazilian merganser.

Further genetic research is currently underway. The goal is to reconstruct the evolutionary history of mergansers within the New Zealand region.

The global origins of New Zealand’s birds

Many New Zealanders believe the country’s native birds originate from Australia. Increasingly though, genetic and palaeontological research shows a number of our feathered friends hail from further afield.

Kiwi are most closely related to the extinct elephant birds of Madagascar, for example. And the extinct adzebill is related to flufftails, also from Madagascar. The extinct moa is most closely related to the tinamou from South America.

The long journey of blue-eyed shags started in South America, with the birds island hopping via Antarctica and the sub-Antarctic islands to New Zealand. Mergansers arriving from the northern hemisphere add another piece to the puzzle.

It is possible that fossils of extinct mergansers (and other birds with distant geographic origins) will be discovered as palaeontologists increasingly focus on previously neglected and newly discovered southern hemisphere fossil deposits.

Only then, combined with the power of ancient DNA, will we be able to fully understand how New Zealand’s dynamic geological, climatic and human history has influenced the colonisation and diversification of birds on this isolated South Pacific archipelago.
The Conversation
Nic Rawlence, Senior Lecturer in Ancient DNA, University of Otago and Alexander Verry, Researcher, Department of Zoology, University of Otago

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Published by The Conversation.
Open access. (CC BY 4.0)
Technical detail and more background is given in the researchers' open access paper in the Zoological Journal of the Linnean Society:
Abstract
Mergansers are riverine and coastal piscivorous ducks that are widespread throughout North America and Eurasia but uncommon in the Southern Hemisphere. One species occurs in South America and at least two extinct species are known from New Zealand. It has been proposed that these Southern Hemisphere merganser lineages were founded by at least two independent dispersal events from the Northern Hemisphere. However, some morphological and behavioural evidence suggests that Southern Hemisphere mergansers may form a monophyletic clade that descended from only a single dispersal event from the Northern Hemisphere. For example, Southern Hemisphere mergansers share several characteristics that differ from Northern Hemisphere mergansers (e.g. non-migratory vs. migratory, sexual monochromatism vs. sexual dichromatism, long vs. short pair bonds). We sequenced complete mitogenomes from the Brazilian merganser and an extinct merganser from New Zealand—the Auckland Island merganser. Our results show that the Brazilian and Auckland Island mergansers are not sister-taxa, and probably descend from two separate colonization events from the Northern Hemisphere at least 7 Mya. Nuclear (palaeo)genomic data may help to further resolve the relationship between living and extinct mergansers, including merganser fossils from New Zealand that have not been subjected to palaeogenetic analysis.


INTRODUCTION
Mergansers (Mergus spp.) are a group of riverine and seasonally coastal fish-eating ducks that have a widespread Northern Hemisphere distribution but are uncommon in the Southern Hemisphere (Kear 2005, Williams et al. 2012, 2014) (Fig. 1). They are characterized by a serrated bill, and include the endangered scaly-sided merganser (M. squamatus Gould 1864) from north-east Asia; the common merganser (M. merganser Linnaeus 1758), and the red-breasted merganser (M. serrator Linnaeus 1758), which have widespread Northern Hemisphere distributions; the critically endangered Brazilian merganser (M. octosetaceus Vieillot 1817); and two currently recognized extinct species from the New Zealand region—M. australis Hombron and Jacquinot 1841 and M. milleneri Williams and Tennyson 2014 from the Auckland and Chatham Islands, respectively. While the hooded merganser Lophodytes cucullatus (Linnaeus 1758), previously M. cucullatus, from North America has a serrated bill, it is not considered a ‘true’ merganser (e.g. Buckner et al. 2018, Lavretsky et al. 2021). The taxonomic relationship of the smew Mergellus albellus (Linnaeus 1758) from Eurasia is currently unresolved; it is sometimes suggested to be more closely related to Mergus and Lophodytes or to goldeneyes (Bucephala spp.) (Livezey 1995, Buckner et al. 2018, Lavretsky et al. 2021).
Figure 1.
Schematic of the breeding distributions of Mergus spp. The New Zealand (NZ) lineage encompasses the Auckland Island merganser (465 km south of NZ) and Chatham Island merganser (785 km east of NZ), as well as Mergus spp. from mainland NZ. Breeding distributions are based off the Cornell Lab of Ornithology Birds of the World website.
The now extinct Auckland Island merganser M. australis (or miuweka) (Fig. 2) was formally described in 1841, based on a specimen collected on the sub-Antarctic Auckland Islands, 465 km south of mainland New Zealand. Rare Late Holocene-aged merganser bones have been found in coastal sand dune deposits (including Māori middens) on New Zealand’s three main islands (Stewart, North, and South), and the Auckland and Chatham Islands (Tennyson and Martinson 2007, Williams et al. 2014, Tennyson 2020). Bones from the latter were recently described as a distinct species M. milleneri, which was smaller than the nominate M. australis, with a shorter skull, relatively shorter premaxilla, smaller sternum and keel, relatively shorter wing bones, and a narrower pelvis (Williams et al. 2014). The taxonomic status of merganser bones from mainland New Zealand is unresolved (i.e. cannot be assigned to either M. australis or M. milleneri), and are currently recognized as Mergus spp. (Birds New Zealand Checklist Committee 2022).
Figure 2.
In the Southern Hemisphere, mergansers are only known from the New Zealand region and South America, represented here by the Auckland Island merganser. A, artistic reconstruction by J.G. Keulemans from Buller (1888); B, historical museum skin (Museum of New Zealand Te Papa Tongarewa OR.001357); C, the Brazilian merganser (photo by Savio Freire Bruno CC BY-SA 3.0).
Mergansers in the New Zealand region are mainly thought to have occupied a riverine and seasonally coastal habitat (e.g. sheltered bays during winter; Kear 2005, Williams et al. 2012, 2014). It is likely that they mainly nested in tree cavities, but also caves in some instances, as the remains of adults, chicks, and eggs have been found within a cave on the Chatham Islands (Williams et al. 2014). By the 17th century, mergansers had been extirpated from the Chatham Islands and mainland New Zealand, and survived only on the Auckland Islands. A combination of subsistence hunting, and predation from the Pacific rat (Rattus exulans) and Polynesian dog (Canis familiaris), probably led to the extinction of mergansers across most of their prehistoric range (Tennyson and Martinson 2007, Greig and Rawlence 2021.1). On the Auckland Islands, predation from introduced pigs (Sus scrofa) and cats (Felis catus), and collecting for the museum trade, resulted in their extinction—indeed the last known Auckland Island merganser specimen was shot and collected in January 1902 (Williams 2012.1).

The only extant merganser in the Southern Hemisphere—the critically endangered Brazilian merganser (Fig. 2)—is one of the rarest birds in the world, comprising only 250 wild individuals. It is split across three remnant populations in Brazil, but once had a more widespread historical distribution encompassing Argentina and Paraguay (Vilaca et al. 2012.2, Maia et al. 2020.1). The Brazilian merganser has undergone a significant population bottleneck, yet different remnant populations can still be genetically identified (Maia et al. 2020.1). Like mergansers from the New Zealand region, the Brazilian merganser occupies riverine habitats, and often nests in tree cavities or rock crevasses (Vilaca et al. 2012.2, Maia et al. 2020.1).

It has been proposed that the Southern Hemisphere mergansers were founded by independent dispersal events to the New Zealand region and South America from the Northern Hemisphere (e.g. Livezey 1995). Based on behavioural characteristics, Johnsgard (1961) tentatively assigned the Brazilian merganser as sister-species to a clade comprising the other Mergus species, with the Auckland Island merganser as the sister-species of the common merganser and scaly-sided merganser. In contrast, using morphological characters, Livezey (1989, 1995) assigned the Auckland Island merganser, then Brazilian merganser, as successive sister-species to all other Mergus species, though with weak to moderate bootstrap support. Using mitochondrial DNA (mtDNA) sequences, Buckner et al. (2018) suggested the Brazilian merganser was the sister-species to the scaly-sided merganser, albeit with weak support. However, some evidence suggests that Southern Hemisphere mergansers may be closely related to one another, potentially even sister-species, as they share several behavioural (e.g. non-migratory and long pair bonds) and morphological (e.g. sexually monochromatic) characteristics, in contrast to their Northern Hemisphere congeners (e.g. migratory, short pair bonds, and sexual dichromatism; Livezey 1995). In addition, recent genetic studies of other extinct Southern Hemisphere avian species have also revealed unexpected evolutionary connections between birds from New Zealand, South America, and Africa (e.g. Mitchell et al. 2014.1a, 2014.2b, Boast et al. 2019, Rawlence et al. 2022.1, Verry et al. 2022.2a). As such, the phylogenetic relationships of the Southern Hemisphere mergansers, when their ancestors arrived in the region, and from where, remain unresolved.

In this study, the first genetic study of a New Zealand Mergus species, we sequenced mitochondrial genomes (mitogenomes) from historical museum specimens from the Auckland Island merganser and Brazilian merganser, and analysed them within a phylogenetic framework of Mergini mitogenomes (Liu et al. 2012.3, Lavretsky et al. 2021). These data were used to determine the phylogenetic relationships and divergence dates within mergansers.

Creationists needn't be too embarrassed by these facts about the distribution and evolution of mergansers, after all, the simple Bronze Age Canaanites who made up the origin myths to fill the gaps in their knowledge and understanding, could have known nothing of them, since they are largely absent from the Middle East, nor of southern hemisphere land masses such as South America, Australia and New Zealand when they didn't even realise there is a southern hemisphere, or of the ducks and their families.

And, of course, they knew nothing about the history of Earth and the life on it, so how could they be expected to have known about the evolutionary history and geographic distribution of these ducks? With their long, serrated beaks and fish diet, they probably wouldn't have recognised mergansers as a type of duck even.

All they had to draw on was their limited knowledge of the small scrap of the globe they inhabited, which is why they got almost everything they described so hopelessly wrong. The lesson from Genesis is just how badly you do when you know little and depend on guesswork from the point of view of someone with the knowledge understanding of a pre-school toddler of today.

Sunday 19 May 2024

Covidiot News - How Regular Vaccine Boosters Are Giving Even More Protection.


Health-care workers received the first doses of the COVID-19 vaccine in December 2020. Repeat booster vaccination with updated versions of the vaccine promotes antibodies against a wide range of variants, as well as related coronaviruses.
Repeat COVID-19 vaccinations elicit antibodies that neutralize variants, other viruses – Washington University School of Medicine in St. Louis

A new study has shown that regular boosters of the COVID-19 vaccines against each new variant, give protection against a broad range of variants probably including variants yet to emerge, as well as related viruses.

This was the conclusion of a study by researchers at Washington University School of Medicine in St. Louis. The concern had been that, like the flu vaccines, earlier vaccinations tend to inhibit the formation of newer antibodies, but the study showed that not only are antibodies raised to the new variant but repeated vaccinations 'train' the immune system to produce a broad spectrum of antibodies.

This very welcome news to someone who has just had his 7th booster but still contracted a mild infection at the end of last summer on a trip to France, especially as we're going to Czechia in a few days’ time.

The research findings are the subject of a pre-edited paper in nature which is sadly behind a paywall, so we only have the Abstract. However, the researchers have provided more detail in a Washington University news release:

Stop The Steal! - How The Christian Far Right Is Stealing America's Democracy


Abraham Lincoln at Gettysburg
… we here highly resolve that these dead shall not have died in vain … and that government of the people, by the people, for the people, shall not perish from the earth.
Most Americans Support Legal Abortion 2 Years After Roe Was Overturned | Pew Research Center

The USA no longer has the government of the people by the people and for the people that the founding fathers intended to create because the Christian far right have decided to take it away as it was not giving them the privileged access to political power to which they feel entitled.

I can say this because, despite the fact that 63% of people support a woman' right to an abortion for any reason, this is now illegal in many states since SCOTUS reversed the decision in Roe vs Wade which gave them that right.

For America to operate as a democracy, the three branches of government - the executive; the legislature and the judiciary should reflect public opinion, not oppose it, yet Donald Trump stuffed SCOTUS with partisan Repugnican fundamentalist Christians and the Rupugnican Party is in bed with Christian far right evangelicals, resulting in a government which is imposing the will of a radical minority on the majority, despite the constitutional bar on the establishment of any religion.

The latest Pew Research poll shows how far this gap between the will of the people and the actions of the government have diverged in respect of the issue of abortion:

Saturday 18 May 2024

Malevolent Designer News - How A Virus Turns Its Bacteria Hosts Into Zombies - And Reduces The Marine Food Supply


Under the microscope, scientists identified SAR11 zombie cells by their distinct lack of ribosomes. In an example comparing a live, infected SAR11 cell to an infected zombie cell: blue indicates bacterial DNA, yellow shows ribosomes, and purple highlights phage genes. The live cell (upper pictures) displays all three colors, while the zombie cell (lower pictures) lacks the yellow ribosome signal. The final column of images on the right merges these colors, clearly distinguishing the two cell types.

© Jan Brüwer/Max Planck Institute for Marine Microbiology.
Zombie cells in the sea: Viruses keep the most common marine bacteria in check

Aficionados of creationism’s malevolent designer will be interested to learn that researchers at the Max Planck Institute for Marine Biology in Bremen, Germany, have discovered a virus that seriously reduces the population of a marine microbe that is an essential part of the marine food cycle, so seriously depleting the food chain for other marine organisms.

The microbe is a bacterium, know to science as a Pelagibacterale or SAR11, and, as an added piece of nastiness, the virus doesn't just infect the bacterium, it turns it into something that is halfway between dead and alive. In other words, it keeps the essential processes working while it uses the parts it needs to make more copies of itself from the bacterium's mitochondrial DNA.

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:

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

Bible Blunder - What The Bible's Authors Could Never Have Guessed At, Again


The box in the ground-based image reveals the location of Hubble’s view within the wider context of this triple-star system. NASA, ESA, G. Duchene (Universite de Grenoble I); Image Processing: Gladys Kober (NASA/Catholic University of America); Inset: KPNO/NOIRLab/NSF/AURA/T.A. Rector

University of Alaska Anchorage/NSF's NOIRLab
Hubble Views the Dawn of a Sun-like Star - NASA Science

Standing in stark contrast with how the authors of the Bible guessed the Universe was like, we have this tiny fraction of it as revealed by the Hubble Space Telescope. It shows some of the earliest stars in formation:

Looking like a glittering cosmic geode, a trio of dazzling stars blaze from the hollowed-out cavity of a reflection nebula in this new image from NASA’s Hubble Space Telescope. The triple-star system is made up of the variable star HP Tau, HP Tau G2, and HP Tau G3. HP Tau is known as a T Tauri star, a type of young variable star that hasn’t begun nuclear fusion yet but is beginning to evolve into a hydrogen-fueled star similar to our Sun. T Tauri stars tend to be younger than 10 million years old ― in comparison, our Sun is around 4.6 billion years old ― and are often found still swaddled in the clouds of dust and gas from which they formed.

As with all variable stars, HP Tau’s brightness changes over time. T Tauri stars are known to have both periodic and random fluctuations in brightness. The random variations may be due to the chaotic nature of a developing young star, such as instabilities in the accretion disk of dust and gas around the star, material from that disk falling onto the star and being consumed, and flares on the star’s surface. The periodic changes may be due to giant sunspots rotating in and out of view.

Curving around the stars, a cloud of gas and dust shines with their reflected light. Reflection nebulae do not emit visible light of their own, but shine as the light from nearby stars bounces off the gas and dust, like fog illuminated by the glow of a car’s headlights.


The Universe as described in Genesis 1: 3-18 and Daniel 8:10.
HP Tau is located approximately 550 light-years away in the constellation Taurus. Hubble studied HP Tau as part of an investigation into protoplanetary disks, the disks of material around stars that coalesce into planets over millions of years.

The description of the Universe as a small, flat planet with a dome over it and stars stuck to the underside of the dome, was the best guess of simple Bronze Age pastoralists who only knew their small area of the Middle East and described what they thought they saw. Of course, that nonsense about the stars shaking loose from the dome and falling to earth during earthquakes was a stretch of the imagination too far. That should have raised doubt in the minds of those who decided to incorporate the Bronze Age pastoralists' naive description in a book they declared to be the inerrant word of an omniscient creator god, but then they probably knew no better themselves.

But now we do, so the ludicrously childish description of the Universe compared to the reality of the Universe as science is now revealing it, should, in the mind of any objective, rational person, raise considerable doubt about the value of the rest of the book, declared by the same compilers to be an accurate record of science and history.
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