The discovery of the oldest known whale bone tools has shed new light on the complex relationship between early human societies and marine mammals. A recent study conducted by researchers from the Institute of Environmental Science and Technology (ICTA-UAB), the French National Centre for Scientific Research (CNRS), and the University of British Columbia has revealed that humans were utilizing whale bones as tools as far back as 20,000 years ago.

This groundbreaking research, led by Jean-Marc Pétillon and Krista McGrath, analyzed 83 bone tools excavated from sites around the Bay of Biscay in Spain, along with 90 additional bones from Santa Catalina Cave. Using mass spectrometry and radiocarbon dating, the researchers identified the species and age of the samples, revealing that at least five species of large whales were used by early humans.

The oldest bone tools date back to approximately 19,000-20,000 years ago, providing some of the earliest known evidence of humans using whale remains as tools. This significant discovery broadens our understanding of early human use of whale resources and offers valuable insights into the marine ecology of the time.

According to Krista McGrath, leading author of the paper, “ZooMS is a powerful technique for investigating past sea mammal diversity, particularly when diagnostic morphometric elements are missing from bone remains and objects.” The researchers were able to identify species such as sperm whales, fin whales, blue whales, and grey whales, which still inhabit the Bay of Biscay today.

Moreover, chemical data extracted from the bones suggest that the feeding habits of these ancient whales differed slightly from those of their modern counterparts. This finding points to potential changes in behavior or the marine environment, further emphasizing the importance of this discovery.

The study not only enhances our understanding of early human use of whale remains but also sheds light on the role whales played in past ecosystems. As we continue to explore and learn from these ancient interactions, we gain a deeper appreciation for the intricate relationships between humans, wildlife, and the environment.

The largest predatory fish to have ever existed, Otodus megalodon, was thought to be primarily focused on whales as their main source of food. However, new research has revealed that these massive creatures had a much broader range of prey than previously assumed.

According to Dr. Jeremy McCormack from the Department of Geosciences at Goethe University Frankfurt, who conducted this study together with scientists from Germany, France, Austria and the US, megalodon’s diet was not as specialized as previously thought. By analyzing fossilized teeth, which are all that remains of these cartilaginous fish, researchers found that megalodon had a flexible enough to feed on various prey from different levels of the food pyramid.

The researchers extracted zinc from the fossil teeth and compared its ratio with other prehistoric and extant shark species, as well as other animal species. This analysis provided insights into predator-prey relationships 18 million years ago. The findings suggested that megalodon was an ecologically versatile generalist, capable of adapting to different food sources depending on availability.

Comparisons between fossils from Sigmaringen and Passau showed regional differences in the range of prey or changes in its availability at different times. This study not only shed new light on the diet of megalodon but also provided valuable insights into how marine communities have changed over geologic time.

As Kenshu Shimada, a paleobiologist at DePaul University in Chicago, USA and coauthor of this study noted, even “supercarnivores” like megalodon are not immune to extinction. Previous studies had suggested that the rise of the modern great white shark was partly responsible for the demise of Otodus megalodon.

In conclusion, this research has revised our understanding of the diet of megalodon and has shown that these creatures were more adaptable than previously thought. The analysis of tooth zinc isotope ratios has proven to be a valuable tool for paleoecological reconstructions and will continue to provide insights into how marine communities have changed over time.

Climate change is posing a severe threat to the habitat of bowhead whales, a threatened Arctic native species. New research has reconstructed an 11,700-year ecological baseline for bowhead whales and projects that sea ice loss will cause their habitat to severely contract by up to 75 per cent by the end of the 21st century.

An international team led by researchers from the University of Adelaide and the University of Copenhagen mapped the location and size of suitable summer foraging habitat for bowhead whales over the entire Holocene. The study used computer models, fossils, and whaling records to find that until recently, this habitat remained constant despite significant climatic fluctuations.

However, the team predicts that future climate change will erode somewhere between 65-75 per cent of this foraging habitat by 2100. In the Sea of Okhotsk, which is home to one of only four populations of bowhead whales, viable summer habitat is likely to vanish entirely by 2060.

The reason for the decline is the collapse of a tight association between bowhead whales and summer sea ice cover. “Bowhead whales have preferred to forage amongst sea ice for many millennia,” said lead author Mr Nicholas Freymueller. However, Arctic sea ice has declined significantly in recent decades, and this is set to accelerate in coming decades.

The study found that the few patches of suitable bowhead habitat predicted to remain in 2100 will exist outside their current distribution, directly impacting conservation policies. “By identifying the extent and location of bowhead whale habitat that is likely to be lost in coming decades, our projections provide vital information to guide future management efforts of this emblematic species,” said Professor Eline Lorenzen.

Bowhead whales are still recovering from four centuries of commercial whaling and are considered emblematic because the ongoing threats they face are reflective of those which all Arctic marine mammal species face due to climate change. The study shows how past perspectives can strengthen predictions of species’ future vulnerability to rapid ocean warming.

This research was published in Ecology and Evolution and provides a critical baseline for conservation efforts aimed at protecting this iconic species from the impacts of climate change.