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Outside of our fellow mammals, our next closest relatives are reptiles. As both birds and mammals are warm blooded (endothermic) and have four-chambered hearts, one might be tempted to think that the sister group to mammals would be birds. But the story is much more complicated than that, especially because birds are actually reptiles.
Reptiles include four main lineages: (1) turtles, (2) lizards and snakes, (3) crocodilians, and (4) dinosaurs, including birds. Indeed, birds are reptiles – birds are a surviving lineage descended from bipedal predatory dinosaurs! In decades past, there were five “classes” of vertebrates (animal groups with backbones): fishes, amphibians, mammals, reptiles, and birds. In fact, many basic treatments still list these groups. For example, Encyclopedia Britannica still has an article entitled: “Five Vertebrate Groups.” But there are major problems with two of these old groups: neither fishes nor scaly reptiles are monophyletic.
This chapter develops a modal structuralist understanding of our experience of time, of causes, and of the robust particularity present in our visual experience of ordinary environmental objects.
I have argued that one of the major misconceptions about evolution and the tree of life is that some species or lineages are considered more “primitive” than others – this chapter will delve more deeply into this misconception and one of its key causes. Across the tree of life, certain lineages – including the platypus, lungfishes, and mosses – are frequently labeled as more primitive than other members of their groups. Mammals provide several good case studies demonstrating the reasons for this longstanding misperception. Researchers, journalists, and filmmakers all seem obsessed with discussing certain lineages that somehow seem primitive to them. This misconception about primitive lineages is problematic for two major reasons. First, it leads to a general misunderstanding of evolution, which can lead to fundamental misunderstandings across all of biology, including human health.
Fossils provide a unique window into how evolution has unfolded. In particular, transitions in the fossil record provide compelling evidence for how major evolutionary changes have happened. One of the most well-known transitions is from fish-like vertebrates to the first land vertebrates – our earliest tetrapod ancestors. (The word tetrapod refers to the groups of vertebrates with four legs, namely mammals, reptiles, and amphibians.) Paleontologists had known that transitional fossils connecting aquatic and terrestrial vertebrates must exist. There were abundant fossils of vertebrates with fins from around 400 mya, and there were abundant fossils of terrestrial tetrapods with limbs from around 350 mya. But key fossils were missing – those that could show details of how the evolutionary crawl onto land had occurred.
Fossils can reveal large differences between the geographic range that a species could potentially inhabit and the more restricted realized distribution where individuals presently occur. Extant great penguins (Aptenodytes Miller, 1778) include emperor and king penguins, which have polar and subpolar ranges, respectively. New evidence now reveals that the fundamental niche for great penguins includes much warmer environments. Here, we report the first skull of an extinct great penguin that lived in Zealandia during the mid-Piacenzian Warm Period (mPWP) when global temperatures were ~3°C above those of the preindustrial era. Because estimated sea-surface temperatures in Zealandia during the mPWP were 10–20°C warmer than those experienced by living emperor and king penguins, we hypothesize that the exclusion of great penguins from lower latitudes today reflects constraints more complex than climate pressures alone. Terrestrial predation might be an overlooked factor because Aptenodytes appears to have gone extinct in Zealandia coincident with the arrival of large raptors like Haast’s eagle, Hieraaetus moorei (Haast, 1872), and Forbes’ harrier, Circus teauteensis Forbes, 1892.
This review examines the relationship between diet and functional dyspepsia (FD), a prevalent disorder of gut–brain interaction affecting 8% of the global population and characterised by postprandial fullness, early satiety and epigastric pain or burning. Despite 40–70% of FD patients reporting symptom onset within minutes of eating, standardised dietary recommendations remain limited. The pathophysiological mechanisms underlying food-related symptoms in FD involve complex interactions between altered gastric accommodation and emptying, visceral hypersensitivity, duodenal immune activation and small intestinal microbial dysbiosis. Current evidence most strongly supports dietary lipids as potent triggers of dyspeptic symptoms, likely mediated through cholecystokinin pathways and heightened visceral sensitivity. Additionally, emerging research indicates potential benefits of fermentable carbohydrate restriction, with the low FODMAP (fermentable oligosaccharides, disaccharides, monosaccharides and polyols) diet showing promise particularly for patients with postprandial distress syndrome. Other dietary factors such as alcohol, coffee, food chemicals, bioactive compounds and meal patterns may also influence FD symptoms though current evidence remains insufficient to inform clinical practice. While existing evidence provides a foundation for understanding diet–symptom relationships in FD, significant gaps remain in translating mechanistic insights into personalised dietary recommendations. Future research should focus on developing evidence-based dietary strategies tailored to FD subtypes, ensuring nutritional adequacy while addressing the complex interplay between nutrient sensing, duodenal immune activation and gut microbiota in symptom generation.
This study aimed to identify the best automatic milking system (AMS) parameters and monitoring data for early detection of clinical mastitis in dairy cows and to determine the earliest possible detection within 30 days with the highest predictive accuracy. From August 2021 to February 2022, 55 Holstein cows were monitored for mastitis using physical examination, positive California mastitis test (CMT) and the AMS manufacturer’s software (Delpro®) criteria: milk electrical conductivity ≥ 5.37 mS/cm, milk yield ≤ 80%, somatic cell count (SCC) > 200,000 cells/mL and Mastitis Detection Index (MDi) ≥ 2.0. For every cow suspected of mastitis, two other lactating cows were randomly chosen for evaluation to provide a comparison with healthy herd companions. In total, 129 inspections were evaluated: 39 with clinical mastitis and 90 without. Data on milking, milk composition and production from the AMS, and behavioural data from monitoring collars were summarized for the 30 days leading up to the mastitis diagnosis. Thirty measurement parameters were analysed using generalized linear models. Sensitivity, specificity, accuracy, positive predictive value and negative predictive value were calculated. In the final model, significant parameters included: milk production per day (kg), SCC (cells/mL), average flow mean (kg/min), average conductivity (mS/cm), average flow peak (kg/min), average production per milking (kg), milking duration (s), rumination (min/day), panting (min/day) and feeding activity (min/day). From −30 to −10 days, accuracy, sensitivity and specificity varied without a defined pattern. However, from day −9, there was stabilization of the evaluated parameters. Results showed an average accuracy of 79.2%, a sensitivity of 82.5%, a specificity of 78.7%, a positive predictive value of 41.5% and a negative predictive value of 92.2% in predicting mastitis occurrence. In conclusion, using AMS parameters and behavioural data from monitoring collars, it was possible to predict clinical mastitis in dairy cows in an AMS with a 9-day advance notice.
This chapter summarizes the MOUDD theory of phenomenal consciousness, and responds to dualist arguments based on bats, zombies, color inverts, and Mary in her black-and-white room.
If we think of ourselves as the “highest” forms of life, we often think of Bacteria as the “lowest” forms of life. We also think of Bacteria as ancient, “primitive,” and ancestral. As discussed for many other extant branches of the tree of life, these views are misleading. But these views may be especially hard to jettison when thinking of Bacteria – aren’t they more ancestral than we are? But we must always come back to this idea: Bacteria are not our ancestors – they are extant cousins. As will be detailed below, all lineages of organisms descended from the LUCA; the major lineages of life did not descend from Bacteria.
The clade Bacteria includes species that are ecologically essential (e.g., as decomposers that impact the carbon cycle) and that comprise key organisms of our microbiome (e.g., the symbiotic Bacteria normally found on our skin and in our digestive tracts). Bacteria also cause many diseases, including stomach ulcers (Helicobacter pylori), tetanus (Clostridium tetani), and acne (Cutibacterium acnes).
The purpose of this study was to confirm reduced training metrics previously associated with a ketogenic low-carbohydrate (CHO) high-fat diet (LCHF) and investigate their attenuation with caffeine supplementation. At baseline, n 21 elite race-walkers followed a high CHO availability (HCHO) diet and performed a tempo hill session (14 km with a 450 m elevation gain). Athletes were then assigned to either the HCHO or LCHF in a parallel groups design for 3 weeks, where the 14 km tempo hill session was repeated each week. On weeks 2 and 3, in a randomised crossover allocation, all participants received 3 mg/kg caffeine or placebo (gum), 20 min before the session. Race-walking speed, heart rate, ratings of perceived exertion, blood metabolites and Stroop word-colour test metrics were collected. Although LCHF athletes walked faster at baseline compared with HCHO (P = 0·049), the HCHO group improved by week 2 (P = 0·009) and week 3 (P = 0·007), whereas the LCHF group was significantly slower in Week 1 (P < 0·001) and Week 2 (P = 0·026) compared with baseline. During the 14 km hill session, within-group analysis shows that athletes walked significantly faster (P = 0·010) and at a higher percentage of vVO2max (P = 0·007) when using caffeine compared with a placebo. Between-group differences remained present, with HCHO athletes walking at a higher percentage of vVO2max than those adhering to the LCHF diet (P = 0·035). No interaction between supplement treatment and dietary group occurred (P = 0·640). Caffeine supplementation partially reversed the performance impairment associated with an LCHF diet, but training quality remained lower than the combination of caffeine and high CHO availability.
Multiple sclerosis (MS) is a chronic, auto-immune, neurodegenerative condition with increasing global prevalence. People living with MS (plwMS) have reported limited guidance relating to nutrition information. Paired with varied health literacy levels, this makes plwMS susceptible to nutrition misinformation.
Design:
A cross-sectional online social network analysis (SNA) examining nutrition information for MS.
Setting:
A systematic SNA using Twitter/X and YouTube platforms using NodeXL to summarise metrics. Quality was assessed using the QUEST tool. Content analysis of YouTube videos was synthesised into themes for misinformation.
Participants:
Online publicly available social media user posts and video content.
Results:
Twitter/X SNA revealed keywords used most by an account representing 72·8 % of the user network with common diet mentions including Wahls (57 times), paleo (15 times) and ketogenic (11 times). ‘Favourite count’ metrics were strongly correlated with ‘repost count’ (r = 0·83, P = 0·000). Videos which endorsed a diet were more likely to have a lower QUEST score. User engagement metrics were higher for lower quality videos. The quality of online nutrition information relating to MS was moderate (61 %). Physicians were the most likely source of nutrition information endorsing a diet for MS. The content analysis identified a knowledge gap for both medical professionals and plwMS.
Conclusions:
Nutrition misinformation for MS occurs on social media and information quality is variable. Audiences need to be cautioned about users with large followings and evaluate the credibility of all information. This study reiterates the importance of evidence-based information for the MS community.
The family Brachycladiidae (Digenea) is a species-rich taxon restricted to marine mammals, well-known for its associated pathogenic load, but otherwise poorly understood. A major gap in our knowledge is their circulation pathways, as the life cycle has been elucidated only for a single brachycladiid species, Orthosplanchnus arcticus, a parasite of pinnipeds. Our goal was to determine whether small ocellate metacercariae previously reported from the Barents Sea edible cockles (Cerastoderma edule) belong to the brachycladiids. We searched for brachycladiid metacercariae in nine bivalve species across three sub-Arctic Seas. They were found in three cardiid species (Ciliatocardium ciliatum, C. edule, and Serripes groenlandicus) and a scallop, Chlamys islandica. Surprisingly, we discovered numerous brachycladiid metacercariae in a single infected whelk, Buccinum undatum. Obtained molecular genetic data (mitochondrial and nuclear ribosomal) indicated that all these metacercariae belong to O. arcticus. We used statistical analysis to explore potential preferences for the second intermediate hosts in this brachycladiid species. The results suggest that bivalve size, rather than species, more accurately predicts infection patterns with O. arcticus metacercariae. We also found no significant differences in morphology between metacercariae from different bivalve species. As such, O. arcticus exhibits broad specificity for the second intermediate hosts, with larger bivalve individuals showing higher infection rates. We discuss the factors underlying this broad specificity, the benefits of larger bivalve preference, and the unequal contribution of different hosts in the transmission of a parasite. Finally, we highlight the potential zoonotic risk associated with O. arcticus due to human consumption of its intermediate hosts.
Central African great ape populations are in serious decline as a result of poaching, habitat loss and disease. Reliable estimates of population size are urgently needed for informed management action. We estimate the abundance and distribution of central chimpanzee Pan troglodytes troglodytes and western lowland gorilla Gorilla gorilla gorilla populations in the c. 11,000 km2 Dja-Ngoyla Complex in Cameroon, a critical component of the Tri National Dja-Odzala-Minkébé (TRIDOM) transboundary landscape, which covers 178,000 km2. We compare our results with previous site estimates and with other population estimates from the region. We completed 1,096.64 km of line transects (n = 559) in 2021 using the standing-crop nest counts method. The Dja-Ngoyla Complex supported c. 11,787 great apes. Chimpanzee abundance was significantly higher in Dja, and Ngoyla-Mintom supported 71% of the gorilla population. Thirty-seven per cent of the gorilla population and 17% of the chimpanzee population occurred in logging concessions. There was no significant change in the species’ abundance in Dja Faunal Reserve compared to our 2018 estimate using the same methodology. The chimpanzee population density was much higher in Dja and Ngoyla Faunal Reserves compared to other protected areas in the region. There was large variation in great ape densities across logging concessions, and those with implemented management certification schemes supported higher densities. This study also highlights the high risk of Dja’s great ape population becoming isolated. Promoting forest management certification to strengthen wildlife and habitat protection in all logging concessions in the Complex is urgently needed and will also allow local communities to benefit from these forests.
Globally, the use of biological products, including biological control agents, biofertilizers, and bioinoculants, has increased significantly as a strategy to reduce dependence on synthetic inputs and promote sustainable agriculture. However, its effects on soil health are still poorly explored. Therefore, this study aimed to analyse the multifunctionality of biological products in agriculture, focusing on soil health, using a systematic review and bibliometric analysis approach. This analysis involves summarizing their mechanisms of action, categories, and impacts. Parameters such as the number of publications per year, the most cited articles, the frequency of keywords and international scientific collaboration networks between countries were analysed. The results showed an expansion in the number of publications on biological products and biological products over the years, with a significant growth in recent years, with emphasis on Brazil and Russia. The most frequent keywords include ‘biological products’, ‘biological product’, ‘soil’, ‘fungi’, ‘bacteria’, and ‘biological control’, and the most cited articles address topics such as the use of Azospirillum sp. in agriculture, the combined application of biological products to control soil diseases, and the inoculation of seeds with Bacillus subtilis. Although few studies have directly evaluated soil health, the results indicate that biological products are related to improvements in soil health, which stimulate the microbiota and promote greater productivity, thereby positively impacting the physical and chemical properties, highlighting the importance of an integrated approach for soil health.
This study examined the associations between cold and hot food and beverage consumption and various health outcomes among Asians and Whites in the USA. Data were drawn from 212 Asian and 203 White adults (aged 18–65 years) in the Healthy Ageing Survey. Participants reported their frequency of cold and hot drink and meal intake, along with symptoms of depression, anxiety, insomnia and gastrointestinal issues (e.g. gas, abdominal fullness). Multivariable analyses adjusted for confounders were used to assess these associations. Among Asians, higher cold consumption in summer was associated with increased anxiety (β = 0·24, 95 % CI: 0·05, 0·44) and abdominal fullness (β = 0·05, 95 % CI: 0·01, 0·86). In contrast, among Whites, higher winter hot drink intake was linked to lower insomnia (β = –0·23, 95 % CI: –0·42, –0·04) and gas symptoms (β = –0·05, 95 % CI: –0·09, –0·01). Tertile analyses showed that, compared with tertile 1, Asians in the highest tertile of summer cold drink intake had higher insomnia scores (β = 1·26, 95 % CI: 0·19, 2·33), while Whites in the highest tertile of winter hot drink intake had lower depression scores (β = –1·73, 95 % CI: –3·28, –0·18). These associations were stronger among individuals with cold hands but not observed in those without. Findings suggest that the temperature of foods and beverages may influence mental and gut health, underscoring the need to consider temperature-related dietary habits in public health and nutrition strategies, particularly across diverse populations.