Acoustic communication, broadly distributed along the vertebrate phylogeny, plays a fundamental role in parental care, mate attraction and various other behaviours. Despite its importance, comparatively less is known about the evolutionary roots of acoustic communication. Phylogenetic comparative analyses can provide insights into the deep time evolutionary origin of acoustic communication, but they are often plagued by missing data from key species. Here we present evidence for 53 species of four major clades (turtles, tuatara, caecilian and lungfish) in the form of vocal recordings and contextual behavioural information accompanying sound production. This and a broad literature-based dataset evidence acoustic abilities in several groups previously considered non-vocal. Critically, phylogenetic analyses encompassing 1800 species of choanate vertebrates reconstructs acoustic communication as a homologous trait, and suggests that it is at least as old as the last common ancestor of all choanate vertebrates, that lived approx. 407 million years before present.
Despite the unquestionable importance of acoustic communication among vertebrates, our knowledge regarding its origin remains sparse. The current consensus based on available evidence favours a convergent origin of acoustic communication among vertebrates: studies on acoustic sensory abilities show that the morphology in the hearing apparatus and its sensitivity vary considerably among vertebrates1,2,3. This, in addition to observed differences in vocal tract morphology, suggests that acoustic communication likely evolved multiple times, emerging independently among diverse clades3. Phylogenetic analyses used to reconstruct the ancestral state of acoustic communication along the tree nodes, whilst suggestive of multiple origins4, are arguably complicated by missing data from key taxa.
An alternative hypothesis is that acoustic communication has a common and ancient evolutionary origin. In support of this, vertebrate hearing epithelia and cerebral promotor circuits that control vocal behaviours are considered to be homologous and operate in the same hindbrain compartment, respectively5,6,7,8,9. Furthermore, in spite of the variety of sound production mechanisms, all Choanata (Dipnoi (lungfishes) + Tetrapoda) lineages have lungs as the physical source of their calling behaviours.
Among vertebrates, clades that can be easily recognised to produce complex sounds (i.e. frogs, crocodilians, birds and mammals) have been studied extensively (e.g. ref. 10,11,12). However, some vertebrate clades, in contrast, have been assumed to be non-vocal based on limited or sparse data. As a consequence, the absence of concrete evidence for vocal production is sometimes treated as evidence of non-vocal tendencies (e.g. ref. 4). Central to a robust reconstruction of acoustic communication is a systematic documentation of these key, neglected groups.
Here, we investigate the evolutionary origins of acoustic communication in choanate vertebrates combining critical data with phylogenetic trait reconstruction methods using a comprehensive dataset. We assess the acoustic communication abilities in species of diverse vertebrate groups, including Lepidosauria (tuataras, lizards and snakes), non-anuran Amphibia (salamanders and caecilians), Chelonians (turtles) and lungfishes (Dipnoi) that are key to mapping vocal communication in the vertebrate tree of life. Using this dataset combined with data of well-known acoustic clades (e.g. mammals, birds and frogs), we test if the evolutionary origin of acoustic communication is shared among choanate vertebrates. We suggest a single origin of acoustic communication in the last common ancestor of all Choanata over 400 million years before present (mybp).
Origins of acoustic communication
We found widespread evidence for acoustic behaviour among all choanate vertebrates. Our recordings include 53 species that belong to groups often thought to be non-vocal and commonly neglected in vocal communication research (Supplementary data 1). Of these, 50 species are turtles—representing over 54% of all genera and more than 14% of all extant species13. We also recorded tuataras (Sphenodon punctatus), one species of caecilian (Typhlonectes compressicauda), and the South American lungfish (Lepidosiren paradoxa). All recorded species were found to possess a varied acoustic repertoire comprising a number of different sounds (see Figs. 1, 2 and supplementary Data 2 to listen to sounds, and supplementary Data 3 for sound descriptions).
A critical review of the extensive literature focusing on groups often considered to lack acoustic communication resulted in a total of 106 species, including 54 turtles, 14 lepidosaurs, 29 salamanders, four caecilians, four frogs and one lungfish having been reported to engage in vocal communication (Supplementary Data 1).
The African lungfish (Protopterus annectens) has been reported to produce sounds14 and to being able to perceive sounds both in the water and air15. Among the ten families of caecilians, we found evidence of acoustic communication in representatives of four of them (Dermophiidae, Grandisoniidae, Ichthyophiidae and Siphonopidae)16,17,18,19. In salamanders, eight out of 10 families have representatives known to produce vocalisations, with evidence being absent only in Hynobiidae and Rhyacotritonidae18,19,20,21,22. We also found evidence for acoustic communication in all species of frogs of the genera Ascaphus23,24 and Leiopelma24,25,26. Among Lepidosauria, examples of acoustic communication are found in most groups of Gekkota27,28, and in tuataras (ref. 29; present study). Among turtles, we found evidence of acoustic communication in representatives from all families, with some species producing over 15 different types of calls used in various situations, including parental care30,31. These findings confirm that the ability to produce vocalisations is distributed across such groups.
The ancestral-state reconstruction for Choanata recovered the presence of acoustic communication as an unambiguous homologous trait, being present in the common ancestor of all choanate vertebrates (407 mybp), and in the majority of the tree nodes (e.g. tetrapods, amniotes, reptiles; Fig. 1). An ancestral-state reconstruction using a tree containing only turtle genera resulted in the presence of acoustic communication in every ancestor node, except for the Geoemydidae family (Fig. 2). This is likely an artefact of the effect of missing data given the limited representation of species of this clade in our dataset, many of which are endangered and hard to access. Nevertheless, the presence of this trait is unambiguously ancestral among turtles.
Data across the turtle tree of life together with other critical taxa in combination with available evidence across all major tetrapod clades totalling in excess of 1800 species confirms a common origin of sound production and acoustic communication among choanate vertebrates, dating from the Palaeozoic (at least 407mybp). These findings support the hypothesis that innovations in the sound production apparatus among choanates were acquired after the first, common appearance of acoustic communication within this group.
The interpretation of acoustic behaviour as a non-homologous trait proposed in previous research3,4 was driven largely by a lack of information on key groups of animals. That is, analyses of ancestral-state reconstruction are complicated by missing data which can subsequently be treated as evidence of absence. Nevertheless, the recent growth of evidence for acoustic communication among certain tetrapod groups, commonly considered to be non-vocal, such as aquatic turtles (e.g. ref. 31,32, and the data provided by us in this paper), are key in revealing the common ancestry of such behaviour. In fact, including evidence from only 14 species (12 turtles, tuatara and lungfish) to the analysis proposed by Chen & Wiens4 was enough to recover opposite results, that were reinforced by the inclusion of data from our critical study of the literature. The sensitivity of ancestral state reconstruction analyses to the character state of key lineages makes a deeper investigation of poorly studied groups imperative.
Knowledge of the natural history of organisms is fundamental in surveys of the macroevolution of certain features. The intensive documentation of vocal communication in turtles in our study is an example. Recordings, observations and subsequent analyses in a phylogenetic framework suggest the homology of vocal communication across turtles and in the last common ancestor of the clade. This result strengthens our broader conclusions on the origins of acoustic communication among choanate vertebrates. Specifically, by evidencing that acoustic communication is widespread and homologous among all turtle genera, we ensure that analysis with a much less comprehensive sample of this group is trustworthy and not subject to extensive interpretation changes by switching the state character of only a few species.
With the inclusion of several taxa of comparatively understudied groups to the analyses, we show that the use of sounds in communication is not only a homologous but also conserved behaviour, widely distributed among choanate vertebrates. The wide variety of mechanisms of sound production—with some of the most distinguished examples being the bird syrinx33,34, the trombone-like crest of Parasaurolophus dinosaurs35,36, and the sound apparatus of bats and dolphins, capable of producing ultrasounds37—also deserves consideration, in order to reveal the anatomical and physical transformations that must have been involved around a common neurobiological framework of sound production.
The larynx has an important role in tetrapod acoustic production, being the main site of vocal production in most lineages38. Although some of the acoustic structures used by choanate vertebrates do not share their embryological origins with the larynx—for example, the bird syrinx develops from different tissues33,34,39—they all share the use of air circulation in the production of sounds, powered by the lungs (with the exception of Plethodontid salamanders that lost the latter). Additionally, all choanate vertebrates are able to produce laryngeal sounds, including birds, while hissing40.
Furthermore, all vertebrates share the location of motoneurons associated with vocalisations in the caudal hindbrain5,41. Vocal-acoustic and pectoral-gestural signalling also share evolutionary and developmental neural origins5,9,42, which implies a common vocal-sonic central pattern generator in the vertebrate brain5,9,41,43.
Many salamanders, caecilians, lizards and snakes produce complex, modulated sounds44,45, that were not considered acoustic communication in the previous analysis due to its usage being usually applied to inter-specific communication4—e.g. defensive behaviour44,46—or allegedly produced by accident47. However, it cannot be excluded that these sounds could have had a common evolutionary origin to those used for intraspecific communication. The same rationale applies to simpler sounds. Hissing and sniffing sounds produced by most vertebrates, especially amniotes48—and nearly all reptiles28—might also contain more information than what we account for. e.g. non-vocal sounds encode individual signals in birds40 and some colubrid snakes mimic the hiss of vipers49.
Considering the fact that communication is usually multimodal, and the loss of acoustic abilities can quickly happen due to redundancy with other channels such as visual and chemical ones in many taxa50, analyses based on ancestral state reconstruction can be biased due to character interpretation and loss of track caused by recent changes in character state in the tip species. The widespread usage of hissing and sniffing sounds among vertebrates might be further evidence that acoustic communication is a shared character in this group and started before the diversification of sounds and their various usages by different clades. Because we chose more conservative methods that include only sounds that play a role in communication with conspecifics, and excludes inter-specific communication (e.g. defence hisses by snakes and other species), future studies might broaden this scope by including such calls, since hisses, in particular, appear to be common across tetrapods, and are typically defence vocalisations.
If all sounds have the same evolutionary origin, vocalisations produced by clades commonly conceived to have had a secondary development of acoustic communication in previous works, such as non-anuran amphibians and Gekkota, mainly Gekkonidae and Pygopodidae4,28, would be homologous to the ones produced by other vertebrates.
The recovery of a single origin of acoustic communication among vertebrates in our analysis reinforces the need to investigate hissing and sniffing sounds, here not classified as acoustic communication. Investigations on the potential primary homology of these sounds, taking a neurobiological, physiological, and anatomical approach, would be important to shed light on this discussion. Comparative studies on the diversification of calls and vocal apparatus, including different vertebrate groups, are also needed to clarify the question of homology.
Vocalisations are also a widespread behaviour among actinopterygian fishes. In this case, however, it may have evolved recurrently and independently over 30 times during their evolutionary history5,9,51,52,53. Although many are the mechanism of sound production among actinopterygians, swim bladder vibrations seem to be the most widespread and ancient of them53. Considering that the homology of lungs among vertebrates is still debated, with strong evidence for a common origin between the lung and the swim bladder54,55,56, a shared origin of acoustic behaviour between choanates and actinopterygians cannot be ruled-out. In this case, expanding our analysis to include actinopterygians may reveal the origins of acoustic communication to be even older than 407mybp57.
Whilst inferring a common origin of acoustic communication among actinopterygians and choanates may be complicated at present due to lack of data, additional alternative evidence points in the same direction—perhaps a deep homology58 of shared brain mechanisms5,9,41,42,43. Furthermore, the gill arches used by fish as a breathing system evolved into the tetrapod hyoid and laryngeal apparatus, used in many mechanisms that include breathing, feeding and sound production59. Such connections might be modulated by the same or similar brain channels, that might suggest evolutionary continuity9.
A challenge to test the hypothesis of a common origin of acoustic communication among some actinopterygian lineages and choanates will be understanding how the morphological transformations involved in the transition to choanates affected the mechanisms of sound production. Palaeontological data and phylogenetic reconstructions are the most common approaches applied to shed light on the evolutionary transformation of traits. However, to date, palaeontological data that are key to a robust resolution of the origins of acoustic communication among actinopterygians and sarcopterygians are missing48,60. This raises a number of additional questions, but of particular importance: is the acoustic communication of choanates an innovation homologous to the acoustic communication based on the swim bladder observed in fishes? If so, did acoustic communication first appear among actinopterygians or in the event that precedes them—such as in the transition from ‘protochordates’ (~550 mybp, 5)? Integrative comparative studies of embryological development, physiology of vocal apparatus and of vocal neural architecture across brain regions combined with gene expression among taxa will be helpful to trace the evolution of acoustic behaviour among vertebrates. The common ancestral origin of acoustic communication provides further justification for the use of choanate animals as models in the study of the origins of human language and speech.
No general ethics approval was required for this study as it was conducted with animals that were already captive. Nevertheless, approval was granted by specific institutions that required analysis from a committee (includes Chester Zoo, CEQUA and Turtle Island).
Sound recordings and analysis
For underwater sound recordings, we used the OceanBase (developed by the Laboratory of Acoustic and Environment—University of Sao Paulo, in partnership with Bunin tech®), an acoustic recorder specifically designed for underwater noise monitoring. It has a sensitivity of −157 ± 2 dB rel 1 V/uPa ± 2 dB and a frequency band of 5 Hz–90 kHz. In-air recordings were conducted using a Tascam® recorder DR-100MKIII with a sensitivity of −115.5 ± 0.5 dB rel 13 mV/uPa ± 4 dB and a frequency band of 5 Hz–96 kHz.
Recordings were made in captivity using plastic pools to ensure that all sounds were produced by the animals being recorded. Each species was recorded for at least 24 h, capturing both day and night activity. We aimed for recording males and females in different life stages whenever specimens were available. We also recorded ambient sound without the presence of any animals in order to account for possible noise/interference.
Sounds recorded were analyzed using Raven Pro 1.661 and Praat62. Sounds were measured using six acoustic parameters: Number of bouts, fundamental frequency (Hz), minimum frequency (Hz), peak frequency (Hz), duration (s), and sound type (simple or complex). These parameters were only used as a first description of the repertoires, and were not subjected to any analysis in the present study.
Acoustic communication data
We recorded 53 species, that include 50 turtle species, one caecilian, one lungfish and tuataras, of which all communicated acoustically (Figs. 1, 2, Supplementary Data 1–3 and Supplementary Note 1). Apart from the vocalisations we recorded, most of the acoustic communication data used in this work originates from the dataset published by Chen & Wiens4, that includes 1799 tetrapod species (supplementary Data 4). In addition, we searched for information on acoustic communication among groups that are often considered to be silent (i.e. Testudines, Lepidosauria, Gymnophiona, Caudata and some anuran species). We gathered information from peer-reviewed articles, books and personal communication with researches that work directly with the referred groups (Supplementary Data 1). Our search was conducted using Google Scholar and Web of Science between March and November 2021 using the keywords “acoustic communication”, “call”, “vocal communication”, “vocalisation”, “song”, and “sound”, in association with the species’ name and superior taxonomic ranks. The search was conducted following PRISMA63 guidelines (Supplementary file 1).
Sound communication entails not only that the animal is producing a sound, but also that it has communicative significance. To avoid mistakes in determining its significance, and to ensure we are comparing homologous types of acoustic communication, we favoured the hypothesis that the presence of a complex repertoire (presence of a number of different sounds and/or harmonic calls) entails communicative meaning and considered only sounds produced by the respiratory tract (excluding scale scratching and tail rattling, for example). We also decided to exclude lungless salamanders of the Plethodontidae family, as they might have a different, non-homologous method of sound production20.
Additionally, in order to ensure character homology, our analysis includes only Sarcopterygian lineages (namely Choanata: Tetrapoda + Dipnoi; ref. 64), as we hypothesised the presence of lungs as a major driver for acoustic behaviour in this clade. Sound production systems in other vertebrate clades are diverse and we have not yet enough evidence to infer its homology.
Sounds produced during defensive behaviour such as hissing and sniffing in lizards or bellowing in snakes were not considered to be intraspecific acoustic communication and, therefore, were not included. Although these behaviours might have a common origin to the sounds here considered acoustic communication, we lack evidence to support this claim and opted for a more conservative approach. Only sounds that were considered by literature reports to be used by the studied species in intraspecific communication were considered.
Compiled information regarding amphibians and reptiles that, in discordance with common beliefs, are capable of producing sounds, were compiled (Supplementary Data 1).
Two different phylogenies were used in this work. In order to analyze the origins of acoustic communication among choanate vertebrates, we used the tree from ref. 57, modified by ref. 4. Besides including representatives of all clades of tetrapods in the family level in a proportional sampling, it matches the available information on acoustic communication for 1799 species4. We made a minor modification to the tree by including Dipnoi as the extant outgroup to Tetrapoda (Choanata). We used the lungfish (Lepidosiren paradoxa) as the sister taxon to all tetrapods and inserted a branch length of 407mybp, based on Eoactinistia foreyi, the oldest coelacanthimorph, from the Devonian57,65.
In the second analysis, we used the turtle phylogeny proposed by Pereira et al.71. This is not the most recent phylogeny available72, but it is the one with the largest overlap with our dataset. In any case, the relationship among genera is the same in both trees. We used the function drop.tip from the Ape package73 in R platform74 to exclude terminals. A tree containing each living turtle genus was created and used to analyze the distribution of sound production among turtles.
We based our analysis for choanate vertebrates on the dataset compiled by ref. 4. We reassigned character states based on the information gathered in our literature search and our own recordings: 0 for the absence of acoustic communication (which is, in many cases, no more than the absence of information) and 1 for presence. The same analysis was used for the turtle genera tree. Character states assigned to each species can be found in Supplementary Tables 5, 6, respectively.
Considering the great amount of missing data regarding turtle vocal behaviours, we inferred the presence of acoustic communication to a genus whenever at least one of its representatives is known to do so. The evolution of acoustic communication was inferred for each ancestral node across-tree using maximum-likelihood reconstruction, and the equal-rates model (ER).
Further information on research design is available in the Nature Research Reporting Summary linked to this article.
The authors declare that the data supporting the findings of this study are available within the paper and/or its supplementary information files: Supplementary Data 1 contains the list of species and corresponding sources obtained in the literature search. Sound repertoires of the species recorded in the present work can be found in Figs. 1, 2 and in detail in Supplementary Data 2 or in an online interactive presentation (shorturl.at/cwMU2). Supplementary Data 3 contains the description of the repertoires and the conditions in which each species was recorded. Supplementary Note 1 includes the PRISMA workflow with the methods used in the literature search, together with the resulting list of references. The literature search was conducted through the platforms Web of Science (https://clarivate.com/webofsciencegroup/solutions/web-of-science/) and Google scholar (https://scholar.google.com/). Supplementary Data 4, 5 contain the character coding information used in the choanate and the turtle analyses, respectively. Code and input files can be found in Supplementary Code 1.
This study used available R packages rather than custom coding. Nevertheless, we provide code and input files in the supplementary material. All code used for this work is provided in Supplementary Code 1.
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Swiss Government Excellence Scholarship (ESKAS) supported G.J.-C. (Grant number: 2020.0190). This work was supported by SNF Grant No. 31003A‑169395 to M.R.S.-V. and by the Federal Commission for Scholarships for Foreign Students (FCS, Switzerland) to G.J.-C.
We thank Belize Foundation for Research and Environmental Education (BFREE) and Patrik Viana for Dermatemys and Typhlonectes photos, respectively; We thank Chester Zoo—Gerardo Garcia and the herpetology team, Turtle Island—Specially Maddy Wheatley and Lisa Marschnig, Centro de Estudos de Quelônios Amazônicos (CEQUA), Jansen Zuanon, Patrik Viana and Danilo Castanho for providing access to specimens. We also thank Dr. Torsten Scheyer and Lucas Sacheli Santos Parra for revising the manuscript and helping with the figures, respectively.
The authors declare no competing interests.
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Nature Communications thanks W. Tecumseh Fitch and the other, anonymous, reviewer(s) for their contribution to the peer review of this work. Peer reviewer reports are available.
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Jorgewich-Cohen, G., Townsend, S.W., Padovese, L.R. et al. Common evolutionary origin of acoustic communication in choanate vertebrates.
Nat Commun 13, 6089 (2022). https://doi.org/10.1038/s41467-022-33741-8
Nature’s Ultra-Rare Isotopes Can’t Hide from this New Particle Accelerator
A new particle accelerator at Michigan State University is producing long-awaited results. It’s called the Facility for Rare Isotope Beams, and it was completed in January 2022. Researchers have published the first results from the linear accelerator in the journal Physics Review Letters.
Physicists sometimes describe isotopes as different flavours of the same element. An atom of any element always has the same number of protons in its nucleus, but the number of neutrons can vary. Atoms of the same element with different numbers of neutrons are called isotopes. Carbon, for example, always has 6 protons, and its atomic number is 6. But there are different isotopes of carbon, each with a different number of neutrons, varying from 2 to 16.
There are only two long-lived and stable isotopes of carbon: carbon-12 (12C) and carbon-13 (13C). Neither one decays, while all other carbon isotopes do. Some carbon isotopes last only a few thousand years; others exist for only the briefest moments. It’s the same with isotopes of other elements. And whether an isotope lasts for trillions of years or a trillionth of a second, its existence plays a role in nature.
Isotopes are essential in understanding many things in nature, including astrophysical objects like neutron stars and the nature and history of our Solar System. Scientists compare isotope ratios in different objects to see how they might be related. Scientists sometimes call the different ratios “fingerprints” because they fulfill a similar evidentiary role. For example, scientists measured the isotope fingerprints of Earth and compared them to Apollo lunar samples to understand how the Moon formed.
Physicists have been studying and identifying isotopes for over a century. With the advent of more powerful particle accelerators, researchers have identified isotopes that exist only for nanoseconds. It takes extremely high energy levels to produce these elusive atoms and sophisticated detectors to measure them. This is where the Facility for Rare Isotope Beams (FRIB) comes into play.
Only about 250 isotopes of all types of atoms exist naturally on Earth. But theory predicts the existence of 7,000 of them, and researchers have already found about 3,000. FRIB is designed to close the gap between those numbers. Calculations predict that the accelerator will find 80% of all theorized isotopes. When its work is completed, the Chart of the Nuclides will list about 6,000 isotopes.
FRIB is made of three segments totalling 488 meters (1600 feet long), folded into a paper-clip shape. In the first stage, stable atoms of selected elements pass through a gas of electrons. The gas strips electrons from the atoms, leaving positively charged ions.
Then FRIB accelerates the positive ions to about half of the speed of light before directing them into their target. As the stream of ions strikes the target, the collision makes the ions lose or gain protons and neutrons. That makes them unstable, producing thousands of rare isotopes, some of which last for only brief moments.
Before they can decay, the isotopes pass through a series of magnets acting as separators. They filter out isotopes by momentum and electrical charge. What remains are the isotopes desired for a particular experiment, which reach FRIB’s suite of instruments that measure the nature of the particles.
Researchers can’t direct FRIB to produce specific isotopes. It’s all based on probabilities. Scientists say that creating the rarest of isotopes in FRIB faces long odds: 1 in 1 quadrillion. But FRIB produces so many collisions and isotopes in a single run that 1 in 1 quadrillion isn’t insurmountable. The mass production of collisions and isotopes led to the prediction that the accelerator could produce 80% of all theorized isotopes.
FRIB has already run two experiments. The first was run at only 25% of the accelerator’s full power. It created a beam of Calcium-48 and directed it into a beryllium target. This resulted in about 40 different isotopes reaching the detectors. By measuring the time of arrival, what isotope it was, and how long it took to decay, the experiment detected five new half-lives for exotic isotopes of phosphorus, silicon, aluminum, and magnesium. Measuring these half-lives provides insights into different models of the atomic realm.
Researchers from multiple institutions took part in the first experiment. The lead spokesperson for the first experiment is Heather Crawford, a physicist at Berkeley Lab. A new paper in the Physical Review Letters presented the results.
The second experiment was directed at understanding neutron stars. Neutron stars are stellar remnants, the collapsed cores of stars that exploded as supernovae. Neutron stars are made of extraordinarily dense matter and no longer undergo fusion. There’s still a lot going on in neutron stars, and there’s much theorizing about how they function. Scientists know that neutron stars contain rare isotopes of scandium, calcium and potassium.
In this experiment, researchers produced a beam of selenium-28 to produce the same rare scandium, calcium, and potassium isotopes. This experiment began in June, and the results haven’t been published yet. But it shows how FRIB can address fundamental questions about some of nature’s most extreme objects.
FRIB can address other questions, not all related to astrophysical objects. Some of its research should shed light on more practical concerns.
In the past, research into nuclear science has produced results that have reduced suffering and shaped people’s lives. Medical imaging technologies like Magnetic Resonance Imaging (MRI) and Positron Emission Tomography (PET) are the results of basic research into nuclear physics. So are smoke detectors, something so simple, effective, and inexpensive they can easily be taken for granted. It’s impossible to calculate how many lives smoke detectors have saved and how much tragedy they’ve prevented. Same with MRI and PET.
Scientists are hopeful that research at FRIB can make similarly valuable contributions to society. History shows us that we can’t always predict the practical benefits of basic research like this but that civilization would look very different without it.
When American physicist Isidor Isaac Rabi developed a way to measure sodium atoms’ movement and magnetic properties, he wasn’t thinking about imaging the insides of human bodies. But as his work and the work of other scientists continued, scientists understood that they could use these measurements and other advances to eventually detect cancer. This work led to the development of MRI, a commonplace medical technology in our world. (Rabi eventually won the Nobel Prize in Physics for his discovery of nuclear magnetic resonance.)
Is it too much to hope that FRIB can somehow contribute to medical science? Not at all, though there are no specifics right now. But the history of one type of cancer treatment is another case study of how research into nuclear physics has reduced suffering. It’s called proton beam therapy.
Proton beam therapy allows for higher doses of radiation to be given to children and sensitive tissues like livers, eyes, and optic nerves. It can target cancer cells more precisely and avoid damaging healthy cells.
It stems directly from research at the Harvard Cyclotron Laboratory in the 1940s. In fact, the first proton beam therapy was given to patients with particle accelerators built for research, not medicine. Now proton beams are regularly used to remove eye tumours, among other things.
Will FRIP eventually treat patients? No. That’s highly unlikely.
But history shows that if we want to make advances that reduce suffering, facilities like FRIP can play a significant role.
FRIP was built to learn about some of nature’s most fascinating objects, like neutron stars. Our understanding of physics is incomplete, and researchers at FRIP intend to fill in some of the blanks. The rest of us get to come along for the ride, and that’s a win for intellectually curious people everywhere.
And if some of what we learn is applied to our everyday lives, that’s a win, too.
Gaze Slack-jawed at the Haunting Beauty of Galaxy NGC 1566, Captured by JWST
Here’s an absolutely stunning new view from the James Webb Space Telescope of a dusty spiral galaxy, NGC 1566. Amateur (but expert!) image editor Judy Schmidt took the raw data from JWST’s Mid-Infrared Instrument (MIRI) and teased out this eerie, spider-web-like view of this distant galaxy. The swirling and symmetrical arms are so full of dust that not many stars are visible.
The reddish areas correspond with star formation, however, Schmidt explained, which shows how the physics of star formation is intertwined with the amount of dust and gas in a galaxy. Additionally, the small central nucleus of NGC 1566 is extremely bright, which is a telltale sign of it being among the Seyfert class of galaxies. The centers of these galaxies are very active and luminous, emitting strong bursts of radiation and potentially harboring supermassive black holes that could be many millions of times the mass of the Sun.
NGC 1566 is located approximately 40 million light-years away in the constellation of Dorado. This is an intermediate spiral galaxy, which means its shape is somewhere between a barred spiral galaxy (like our Milky Way) and a regular spiral galaxy.
Schmidt said on Twitter that the muted colors in this image come from the various emission of dust.
“I had to increase the saturation tremendously to make it colorful at all. The separation is not very much otherwise,” she said, adding that this all “took a bit of doing this time because the pipeline images available from the archive had a lot of alignment issues. I had to manually mosaic this.”
The image comes from JWST’s Early Release Program, where immediate access is available to data from specific science observations from JWST, completed within the first five months of the telescope’s science operations.
Compare JWST’s mid-infrared view with an earlier Hubble image taken by Hubble’s Wide Field Camera 3 (WFC3) in the near-infrared part of the spectrum.
Hubble Space Telescope captures stunning bridge of stars
Stretching like a celestial bridge across space, Arp 248 — also known as Wild’s Triplet — is a spectacular sight for keen-eyed astronomers.
The Hubble Space Telescope offers a new view of the mesmerizing trio in a photo released on Oct 31 that shows the dynamism of tidal tails at play, according to a statement (opens in new tab) from the European Space Agency, a partner on the mission. A tidal tail is an elongated trail of gas, dust, and stars formed by the mutual gravity of the two galaxies. In the new image, a tidal tail from one of the two foreground galaxies appears to connect the pair of galaxies, while the third galaxy in Wild’s triplet is just outside of the frame of the Hubble photo.
The two foreground galaxies in Wild’s Triplet are located about 200 million light-years from Earth in the constellation Virgo. The unrelated galaxy in the background is much farther away and isn’t interacting with the triplet. The system was first discovered by astronomer Paul Wild in 1953 while working with Fritz Zwicky at Caltech.
The trio is included in both “A Catalogue Of Southern Peculiar Galaxies And Associations,” produced by astronomers Halton Arp and Barry Madore, and “Atlas of Peculiar Galaxies,” by Arp. These collections feature unusual galaxies, including Arp 248 alongside galaxies with odd numbers of arms, peculiar structures and more.
Hubble is working its way through the galaxies included in the catalogs. The Wild’s Triplet photo comes from its Advanced Camera for Surveys, which is searching for potential candidates for follow-up observation using more sophisticated instruments, like the James Webb Space Telescope and the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile.
Given the overwhelming number of objects in the sky that scientists could study, projects such as Hubble’s tour of Arp galaxies are helpful in narrowing down targets for more in-depth observations, since the limited amount of telescope time available to astronomers makes that time very precious. Knowing in advance that something about a target sets it apart from the rest is a great way to narrow things down and make the best use of limited resources.
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