AI Models Identify Biodiversity in Tropical Rainforests

The Banded Ground Cocoo (Neomorphus radiolosus, left) and the Purple Chested Hummingbird (Polyerata rosenbergi) are among the birds recorded in tropical reforestation plots in Ecuador.
Photo Credits: John Rogers / Martin Schaefer)

Animal sounds are a very good indicator of biodiversity in tropical reforestation areas. Researchers led by Würzburg Professor Jörg Müller demonstrate this by using sound recordings and AI models.

Tropical forests are among the most important habitats on our planet. They are characterized by extremely high species diversity and play an eminent role in the global carbon cycle and the world climate. However, many tropical forest areas have been deforested and overexploitation continues day by day.

Reforested areas in the tropics are therefore becoming increasingly important for the climate and biodiversity. How well biodiversity develops on such areas can be monitored very well with an automated analysis of animal sounds. This was reported by researchers in the journal Nature Communications.

Genomic analysis in snakes shows link between neutral, functional genetic diversity

Eastern massasauga rattlesnake.
Photo Credit: Scott Martin

In the world of threatened and endangered species conservation, the genomic revolution has raised some complicated questions: How can scientists justify assessing species genetic diversity without consulting entire genomes now that they can be sequenced? But then again, how can scientists justify the time and expense of genome sequencing when age-old measures of neutral genetic diversity are much cheaper and easier to obtain?

A new study suggests making a transition from “old school” genetics to “new school” genomics for species conservation purposes probably isn’t necessary in all cases.

Researchers found the functional genetic diversity they detected by analyzing gene variations in fully sequenced genomes of 90 Eastern massasauga rattlesnakes correlated nicely with the neutral genetic diversity seen across broad sections of those same genomes containing no protein-coding genes – similar to the type of genetic material historically used to assess genetic diversity. 

“If we’re worried about the genetic health of populations, neutral diversity can give us a pretty good answer, as has long been argued. We have directly tested that for this species,” said H. Lisle Gibbs, professor of evolution, ecology and organismal biology at The Ohio State University and senior author of the study. 

Space weather disrupts nocturnal bird migration

A Baltimore oriole in flight. Orioles are nocturnal migratory birds.
Photo Credit: Andrew Dreelin

It’s well-known that birds and other animals rely on Earth’s magnetic field for long-distance navigation during seasonal migrations.

But how do periodic disruptions of the planet’s magnetic field, caused by solar flares and other energetic outbursts, affect the reliability of those biological navigation systems?

University of Michigan researchers and their colleagues used massive, long-term datasets from networks of U.S. Doppler weather radar stations and ground-based magnetometers—devices that measure the intensity of local magnetic fields—to test for a possible link between geomagnetic disturbances and disruptions to nocturnal bird migration.

They found a 9%-17% reduction in the number of migrating birds, in both spring and fall, during severe space weather events. And the birds that chose to migrate during such events seemed to experience more difficulty navigating, especially under overcast conditions in autumn.

The new findings, published online Oct. 9 in Proceedings of the National Academy of Sciences, provide correlational evidence for previously unknown relationships between nocturnal bird migration dynamics and geomagnetic disturbances, according to the researchers.

Feather-tailed possums in New Guinea were originally Aussies: fossil study

The New Guinean feather-tailed possum, Distoechurus pennatus, never developed gliding.
Photo Credit: UNSW Sydney

Scientists have long known that the miniature feather-tailed possums in Australia and the island of New Guinea – members of the marsupial family Acrobatidae – were evolutionary cousins, but where they started their long evolutionary journey has been a bit of a mystery – until now.

According to recently published research in Alcheringa: An Australasian Journal of Paleontology, paleontologists from UNSW Sydney say the modern-day animals on either side of the Torres Strait came from common ancestors in Australia before diverging into their living gliding and non-gliding descendants, known as Acrobates pygmaeus in Australia and Distoechurus pennatus in New Guinea.

Professor Mike Archer from UNSW’s School of Biological Earth and Environmental Sciences says that in an analysis of extinct species found at Riversleigh World Heritage Area fossil deposits in north-western Queensland revealed that ancestors of both groups of possums were present in Australia by at least 25 million years ago.

“As Riversleigh started revealing its prehistoric treasures, we discovered four different species of feathertail possums, the first ‘deep-time’ fossil record known for the whole family,” he says.

Curtin study suggests rare echidna noises could be the ‘language of love’

Echidnas, sometimes known as spiny anteaters, are quill-covered monotremes (egg-laying mammals) belonging to the family Tachyglossidae
Photo Credit: Emmanuel Higgins

Curtin University researchers have captured rare recordings of echidnas cooing, grunting and making a range of other sounds, but only during the breeding season.

Lead author Dr Christine Cooper, from Curtin’s School of Molecular and Life Sciences, said there had been ongoing scientific debate around the ability of echidnas to vocalize as a way of communicating or if the sounds they make are simply sniffing noises related to breathing.

“We observed wild short-beaked echidnas at Dryandra National Park, near Narrogin, Western Australia, making cooing and grunting sounds, in addition to the wheezing and exhalation noises that the animals are known to make,” Dr Cooper said.

“Our team managed to capture some of these sounds with hand-held microphones as well as a camera and microphone left unattended at the entrance to a cave popular with echidnas.

Study shows birds that have evolved greater complexity are less biodiverse

Songbirds have less complex skeletons and are species rich
Photo Credit: cocoparisienne

A new study of the evolution of birds shows that as their skeletons become more complex, they also decrease in diversity, with fewer species as they become more specialized in their niches. The findings, published in Nature Communications, show a correlation between skeleton complexity and bird diversity for the first time, and help biologists better understand why biodiversity varies across the birds.

Researchers at the Milner Centre for Evolution at the University of Bath looked at 983 species across all major groups of living birds and measured the complexity of their skeletons by comparing the bones in their fore limbs (wings) and hind limbs (legs).

They found that less complex birds - those with a smaller difference between their fore and hind limbs - had more species diversity than those with higher complexity and a larger difference between their limbs.

For example, birds such as pigeons, gulls and songbirds (passerines) have low skeletal complexity but a high diversity of species living in varied habitats across the world.