University of Granada

A team in the United States has analysed how exposure to environmental chemicals in previous generations influences the onset of the first menstruation. The researchers used data from the California Child Health and Development Study (CHDS) and analysed blood samples taken from 250 pairs from the 1960s. The results, presented at the annual meeting of the Endocrine Society in San Francisco (USA), show that although the average age of first menstruation remained stable between grandmothers and their daughters, it decreased by one year between daughters and granddaughters. Certain chemicals present in the blood of the mother and father were linked to the onset of puberty in their descendants, with stronger effects in granddaughters, according to the study, and with greater weight of male exposure.

An international study with 72 participants has found that greater connectivity between certain brain areas is associated with greater mathematical computational ability. In addition, weak electrical stimulation in a particular area was associated with improved computational learning in volunteers with lower connectivity. The results are published in the journal Plos Biology.  

Lead exposure in children can affect their neurodevelopment. In the United States, the maximum blood concentration limit for this metal was lowered to 3.5 μg/dL (micrograms per decilitre) in 2021, down from 10 μg/dL in 2012. Now, a study has analysed data from more than 300,000 children in Iowa and found an association between higher concentrations and poorer school performance in reading and maths, even below the 3.5 μg/dL limit, prompting the researchers to reconsider this figure. The results are published in the journal JAMA Network Open.

A team has analysed data from a survey of more than 3,000 teenagers aged 11-19 in the UK. Their findings show that those with mental health problems spend an average of 50 minutes more per day on social media than those who do not suffer from them. According to the authors, who publish the results in the journal Nature Human Behaviour, further research is needed to know if this is a causal relationship.

An Australian team has conducted a study involving mice and humans that suggests that vaccine boosters would be more effective if administered in the same arm as the previous dose, at least in the short term. However, other recent research has pointed in the opposite direction. The results are published in the journal Cell.

Two international teams have independently discovered the presence of oxygen in the galaxy JADES-GS-z14-0, the most distant known. The finding, which has been made using the ALMA telescope at the European Southern Observatory (ESO), could mean that galaxies evolved much earlier than previously thought. The results are published in the journals Astronomy & Astrophysics and The Astrophysical Journal.

A fragment of a human face discovered in 2022 at the Sima del Elefante site in the Sierra de Atapuerca (Burgos) and dated to between 1.1 and 1.4 million years ago represents the oldest known face in Western Europe. The fossil, nicknamed ‘Pink’, does not belong to Homo antecessor, but has been provisionally catalogued as Homo affinis erectus. The find, which is published in the journal Nature, could indicate that Western Europe was populated by at least two species of hominids during the Early Pleistocene: Homo affinis erectus and, later, Homo antecessor.

The 16th meeting of the United Nations Conference on Biodiversity (COP16) in Rome has concluded with an agreement to adopt the first global plan for financing nature conservation, after three days of meetings. This meeting meant resuming the negotiations that began last October in Cali (Colombia), where the parties failed to reach an agreement on how to finance the Kunming-Montreal Global Biodiversity Framework reached at COP15, which aims to protect a third of the land and oceans by 2030.

One study suggests that conservation efforts are concentrated around a small number of charismatic species, such as elephants. However, there are undervalued species, such as fungi, plants and invertebrates, that are critical to the functioning of ecosystems. The research, published in the journal PNAS, analysed more than 14,000 conservation projects spanning a 25-year period - from 1992 to 2016. Of the nearly $2 billion allocated by the projects, 83% went to vertebrates. Plants and invertebrates each received 6.6% of the funding, while fungi and algae received less than 0.2%.

According to a new study published in Science, a machine learning-based artificial intelligence (AI) system - called Mal-ID - can decipher an individual's history of infections and diseases in the immune system. The authors say this provides a powerful tool with the potential to accurately diagnose autoimmune disorders, viral infections and vaccine responses.