Thursday, September 1, 2022

Finnish Nationally Representative Student Sample: Reactions to minor-older and minor-peer sex as a function of personal and situational variables, author argues, contradict the trauma view often applied

Reactions to Minor-Older and Minor-Peer Sex as a Function of Personal and Situational Variables in a Finnish Nationally Representative Student Sample. Bruce Rind. Archives of Sexual Behavior volume 51, pages 961–985, Jan 11 2022. https://link.springer.com/article/10.1007/s10508-021-02224-0

Abstract: Felson et al. (2019) used a large-scale nationally representative Finnish sample of sixth and ninth graders to estimate the population prevalence of negative subjective reactions to sexual experiences between minors under age 18 and persons at least 5 years older and between minors and peer-aged partners for comparison. They then accounted for these reactions in multivariate analysis based on contextual factors. The present study argued that focusing exclusively on negative reactions short-changed a fuller scientific understanding. It analyzed the full range of reactions in the same sample, focusing on positive reactions. For reactions in retrospect, boys frequently reacted positively to minor-older sex (68%, n = 280 cases), on par with positive reactions to boy-peer sex (67%, n = 1510). Girls reacted positively to minor-older sex less often (36%, n = 1047) and to girl-peer sex half the time (48%, n = 1931). In both minor-older and minor-peer sex, rates of positive reactions were higher for boys vs. girls, adolescents vs. children, when partners were friends vs. strangers or relatives, with intercourse vs. lesser forms of sexual intimacy, with more frequent sex, and when not coerced. Boys reacted positively more often with female than male partners. In minor-older sex, partner age difference mattered for girls but not boys, and the minor’s initiating the sex (14% for girls, 46% for boys) produced equally high rates of positive reactions. Most of these factors remained significant in multivariate analysis. The frequency of positive reactions, their responsiveness to context, the similarity in reaction patterns with minor-peer sex, and the generalizability of the sample were argued to contradict the trauma view often applied to minor-older sex, holding it to be intrinsically aversive irrespective of context.

Check also Prevalence and Patterns of Child Sexual Abuse and Victim–Perpetrator Relationship Among Secondary School Students in the Northern Province (South Africa). S. N. Madu & K. Peltzer. Archives of Sexual Behavior volume 30, pages 311–321 (Jun 2001). https://link.springer.com/article/10.1023/A:1002704331364

Abstract: An investigation into the prevalence and characteristics of child sexual abuse in the Northern Province (South Africa) was conducted. A total of 414 secondary school students in standard 9 and 10 in three representative secondary schools completed a retrospective self-rating questionnaire in a classroom setting. The questionnaire asked about childhood sexual abuse and the victim–perpetrator relationship. Results shows an overall (N = 414) child sexual abuse prevalence rate of 54.2%, 60% for males (N = 193), 53.2% for females (N = 216). Among them, 86.7% were kissed sexually, 60.9% were touched sexually, 28.9% were victims of oral/anal/vaginal intercourse. “Friend” was the highest indicated perpetrator in all patterns of sexual abuse. Many victims (86.7%) perceived themselves as not sexually abused as a child, and many (50.2%) rated their childhood as “very happy.” A call is made for more research, publicity, and campaigns in the area of child sexual abuse in the Province.

"But a new 10-year study from Palmyra Atoll [...] shows that reefs outside the reach of local human impacts can recover from bleaching." Oh, really! And the recovery was remarkable? Who could have said that...

Decadal stability of coral reef benthic communities on Palmyra Atoll, central Pacific, through two bleaching events. Adi Khen, Maggie D. Johnson, Michael D. Fox, Samantha M. Clements, Amanda L. Carter & Jennifer E. Smith. Coral Reefs volume 41, pages 1017–1029, May 21 2022. https://link.springer.com/article/10.1007/s00338-022-02271-6

Abstract: The prevalence of coral bleaching due to thermal stress has been increasing on coral reefs worldwide. While many studies have documented how corals respond to warming, fewer have focused on benthic community responses over longer time periods or on the response of non-coral taxa (e.g., crustose coralline algae, macroalgae, or turf). Here, we quantify spatial and temporal changes in benthic community composition over a decade using image analysis of permanent photoquadrats on Palmyra Atoll in the central Pacific Ocean. Eighty permanent plots were photographed annually between 2009 and 2018 on both the wave-exposed fore reef (FR, 10 m depth, n = 4 sites) and the wave-sheltered reef terrace (RT, 5 m depth, n = 4 sites) habitats. The El NiƱo events of 2009–2010 and 2015–2016 resulted in acute thermal stress and coral bleaching was observed at both reef habitats during these events. Across 10 yr and two bleaching events, the benthic community structure on Palmyra shows evidence of long-term stability. Communities on the RT exhibited minimal change in percent cover of the dominant functional groups, while the FR had greater variability and minor declines in hard coral cover. There was also spatial variation in the trajectory of each site through time. Coral cover decreased at some sites 1 yr following both bleaching events and was replaced by different algal groups depending on the site, yet returned to pre-bleaching levels within 2 yr. Overall, our data reveal the resilience of calcifier-dominated coral reef communities on Palmyra Atoll that have persisted over the last decade despite two bleaching events, demonstrating the capacity for these reefs to recover from and/or withstand disturbances in the absence of local stressors.


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Popular version

CENTRAL PACIFIC CORAL REEF SHOWS REMARKABLE RECOVERY DESPITE TWO WARM-WATER EVENTS. Scripps Institution, Jul 6 2022. https://scripps.ucsd.edu/news/central-pacific-coral-reef-shows-remarkable-recovery-despite-two-warm-water-events

Excerpts, images and links removed:

The largest global coral-bleaching event ever documented struck the world’s oceans in 2014 and lasted until 2017. The onset of this abnormal whitening condition spawned widespread gloom-and-doom news reports about its calamitous effect on Australia’s Great Barrier Reef and more general predictions of coral reef extinction by 2050. 

But a new 10-year study from Palmyra Atoll in the remote central Pacific Ocean shows that reefs outside the reach of local human impacts can recover from bleaching.

“One year after each bleaching event, we did see signs of coral decline at some of the sites, but within two years this was restored,” said Adi Khen, a Scripps Oceanography PhD candidate and lead author. The research team of current and former members in marine ecologist Jennifer E. Smith’s laboratory saw only a small net change in the reef’s coral and algae populations after a decade. Khen, Smith and four co-authors published their results in the journal Coral Reefs [https://link.springer.com/article/10.1007/s00338-022-02271-6].

“This is a testament to the resilience of Palmyra’s reefs in the context of climate change and demonstrates the capacity for recovery in the absence of local stressors,” Khen noted. “Because we have this long-term time series, we’re able to see perspectives from before and after disturbances.” 

[The Palmyra Atoll is located 1,300 kilometers (about 805 miles) south of Hawaii.]

“During the warming event that occurred in 2015, we saw that up to 90% of the corals on Palmyra bleached but in the year following we saw less than 10% mortality,” Smith reported. “Measuring not just death and destruction but measuring recovery is really important. Seeing the recovery is where we can learn what might help inform future management.”


Smith first visited the Palmyra National Wildlife Refuge in 2005, shortly after it was established. The recent paper includes data that Smith or members of her team, diving in scuba gear, collected at least once annually from 2009 to 2018 during visits to the exact same 80 plots spread across eight sites around the atoll along underwater transects. 

Using simple image-analysis tools and digital tracing, her team then identifies all bottom-dwelling organisms present in the plots to see if they are increasing or decreasing in abundance. It takes from one to two hours for a team of graduate and undergraduate students to process each image. More than 1,500 images have been taken of the plots so far.

[...]

The Palmyra dataset suggests that warm-water events by themselves may cause some decline in reef-building corals and calcifying algae. But the atoll’s clean, protected waters and intact ecosystems harbor a healthy population of fishes that may contribute to the resilience of Palmyra’s reefs.

“These remote, protected reef systems  seem to be able to recover much faster than reefs that are adjacent to dense human populations where overfishing, coastal development, and fresh water runoff containing fertilizers and pesticides all may erode the ability of a reef to recover,” Smith said. 

Most coral reefs are near large human populations in locations beset with pollution, overfishing, sedimentation, warming and acidification.

“Certainly, they’re going to be more susceptible to large losses,” Smith said. “But to know that places like this are out there showing signs of resistance and resilience gives us hope and also shows us that there’s still a lot to learn about how these intact systems are functioning.”

[...]

Since 1892, it has been widely assumed that somatic mutations are evolutionarily irrelevant in animals because they cannot be inherited by offspring; in some corals they found inheritance of somatic mutations

Kate L. Vasquez Kuntz, Sheila A. Kitchen, Trinity L. Conn, Samuel A. Vohsen, Andrea N. Chan, Mark J. A. Vermeij, Christopher Page, Kristen L. Marhaver, Iliana B. Baums. Inheritance of somatic mutations by animal offspring. Science Advances, 2022; 8 (35) DOI: 10.1126/sciadv.abn0707

Abstract: Since 1892, it has been widely assumed that somatic mutations are evolutionarily irrelevant in animals because they cannot be inherited by offspring. However, some nonbilaterians segregate the soma and germline late in development or never, leaving the evolutionary fate of their somatic mutations unknown. By investigating uni- and biparental reproduction in the coral Acropora palmata (Cnidaria, Anthozoa), we found that uniparental, meiotic offspring harbored 50% of the 268 somatic mutations present in their parent. Thus, somatic mutations accumulated in adult coral animals, entered the germline, and were passed on to swimming larvae that grew into healthy juvenile corals. In this way, somatic mutations can increase allelic diversity and facilitate adaptation across habitats and generations in animals.

Popular version: Corals pass mutations acquired during their lifetimes to offspring. August 31, 2022. https://www.sciencedaily.com/releases/2022/08/220831152728.htm


DISCUSSION

By investigating uniparental and biparental, meiotic offspring from the coral A. palmata, we show that somatic mutations at multiple loci, which were acquired over the lifetime of a parent animal, can be inherited by its offspring (Figs. 1 and 2 and fig. S7). These findings were reproducible across two spawning years and in two locations at opposite ends of the species’ range (note S5). Because coral genets can persist for hundreds to thousands of years, somatic mutations can rise to high frequency in modules (polyps) of a genet due to stochasticity or selection (35, 36). Strongly deleterious or lethal mutations might lead to module or colony death, but not genet death, and can thus be removed from the genet’s gene pool while preserving the genet itself. Meanwhile, neutral and beneficial somatic mutations can accumulate in tissues, spread to new modules via polyp budding, and be dispersed over small spatial scales through colony fragmentation [ca. 70 m, (37)]. After these mutations are inherited by offspring, fitness variance is redistributed from the realm of within-colony to between-organism selection. Furthermore, these somatic mutations have the potential to disperse over much longer distances [hundreds of kilometers, (38)] by pelagic coral larvae that have inherited the mutations. Thus, the discovery of heritable somatic mutations in coral offspring represents a previously unconfirmed source for coral adaptation and evolution.

The mechanism by which adult A. palmata transmit somatic mutations to offspring remains to be found (Fig. 4). Mutations may have originated in the soma, dedifferentiated into stem cells, and then redifferentiated into germ cells, or somatic cells may have transdifferentiated directly into germ cells (39). Stem cells have not yet been identified in corals; however, the regenerative properties of anthozoans (40, 41) and the identification of progenitor/undifferentiated cells with stem cell characteristics in a sea anemone (42) and in coral cell lines (43) both point to their existence (19, 35). In any case, the mutations identified and tracked in this study must have occurred after embryogenesis of the primary polyp that founded the genet was complete because the mutations were not shared among all polyps of the adult parent genet or all ramets of the genet. This implies that multipotent progenitor or stem-like cells are not moving freely throughout a colony, setting up competition among cells of different stem cell lineages.


[Fig. 4. Modes of inheritance of genetic mutations in animals.

(1) If animals differentiate and segregate germline cells (light blue) from somatic cells (light orange) early in development, then only germline mutations (medium blue) can be inherited by offspring (1). (2) Planarians, sponges, and some cnidarians continuously segregate a germline and somatic tissue from a population of stem cells (brown) as they grow, allowing for an accumulation of mutations that are heritable (11). (3) Cnidarian somatic cells may de- or transdifferentiate into germline cells, passing on mutations that are somatic in origin (dark blue) (14). The cellular source (soma, germ, or stem) for polyp growth is an active area of research. (4) Somatic mutations (dark orange) may rise to fixation in new modules (polyps) through budding from a limited number of soma cells. Lightning bolts represent mutation-causing events. Figure modified with permission from Reusch et al. (21).]


Immediately after a somatic cell mutates, it undergoes competition with nonmutated cells in a process called developmental selection (36, 44–46). This “struggle of the parts,” as described by Wilhelm Roux in 1881 and later recognized by Weismann as “intraorganismal selection,” is distinct from germline selection (47, 48) and can occur at the molecular, chromosome, or cellular level. Propagation of the somatic mutation then depends on either successfully outcompeting or coexisting with other somatic lineages during cell growth and proliferation (21, 49). Beneficial (or neutral) mutations that survive developmental selection can therefore be disproportionately represented in the cells of a genet (50), an advantage that germline mutations do not have. Somatic mutations with beneficial fitness effects in clonal organisms may be more common than previously thought (51, 52) and may allow ramets to withstand environmental fluctuations. Here, we show that gametes carrying somatic mutations survive to form healthy juvenile corals.

A high percentage of the coral offspring analyzed here were uniparental (73%) compared to previous studies [~1 to 10% uniparental offspring; (53, 54)]. While this is not common in animals nor is it typical for most broadcast spawning corals, uniparental reproduction is common in plants. Plant species frequently switch from biparental to uniparental reproduction when sexual partners are scarce, e.g., at the edges of the species range, when introduced to new habitats, or after large-scale disturbances (55, 56). Hence, like plants, corals may rely on the generation of uniparental larvae to persist during times when sexual partners are rare. Within-genet selection before gametogenesis may effectively purge lethal recessive mutations that would otherwise be exposed to selection only during mating between genets and so reduce the cost of selfing/uniparental inheritance (36, 57). Thus, the production of uniparental offspring that harbor parental somatic mutations might help buffer against the losses of genetic diversity and consequences of inbreeding (56) that would otherwise occur in uniparental mating, i.e., as a result of self-fertilization (32).

Modular species are found in multiple groups (e.g., multicellular algae, fungi, and animals) across the eukaryotic tree of life (21), and a small number of researchers have suggested that somatically generated variation should be considered to understand evolution in these taxa (36, 58). However, the common assumption that Weismann’s barrier is universal in animals (7) has led biologists to disregard somatic mutations as a potentially important source of new genetic variation to shape animal evolution. Our demonstration of transgenerational inheritance of acquired genetic variation challenges this long-held assumption. Like many other modular, long-lived marine invertebrates, terrestrial plants, and even seagrasses, coral genets experience substantial environmental pressures over their long life spans, and somatic mutations may play a major role in their adaptation to these changes (21, 59). Our findings further illustrate the narrowing differences known to exist in the evolutionary dynamics characterizing plants and nonbilaterian animal groups such as corals.


In the US, the 2020 decline in college enrollment was seven times greater for male than for female students; and Finland's internationally acclaimed educational performance is entirely explained by the stunning performance of Finnish girls

Of Boys and Men: Why the Modern Male Is Struggling, Why It Matters, and What to Do about It Kindle Edition by Richard V. Reeves. Aug 2022. https://www.amazon.com/Boys-Men-Modern-Struggling-Matters-ebook/dp/B0B2M164L4

Excerpts:

I was shocked to discover that many social policy interventions, including some of the most touted, don't help boys and men. The one that first caught my eye was a free college program in Kalamazoo, Michigan.  According to its evaluation team, "women experienced large gains," in terms of college completion (increasing by 50%), "while men seem to experience zero benefit."  This is an astonishing finding.  Making college free had no impact on men [...] So not only are many boys and men struggling, they are less likely to be helped by policy interventions.

[...]

In the U.S. for example, the 2020 decline in college enrollment was seven times greater for male than for female students.

[...]

The bottom line is that Finland's internationally acclaimed educational performance is entirely explained by the stunning performance of Finnish girls.