Image Credit: hbieser, Pixabay Licence, Image Cropped
Introduced herbivores restore Late Pleistocene ecological functions (2020) Lundgren et al., PNAS, https://doi.org/10.1073/pnas.1915769117
The fauna of the Pleistocene (also known as the Ice Age) was not that dissimilar to the communities of animals which inhabit our planet now. However, many more large land mammals inhabited all kinds of ecosystems. By the end of the Pleistocene, many of them were extinct, mainly due to climate change impacts (glaciers got larger and restricted their ragne) and prehistoric human impacts like over-hunting, habitat alteration, and introduction of new diseases. The decline of large-bodied herbivores in the Late Pleistocene (LP from here on) led to many ecological changes including reduced nutrient cycling and dispersal, reduced primary productivity, increased wildfire frequency and intensity, and altered vegetation structure. These changes have become our norm.
Scientists usually study species introduction under the premise that they are ecologically novel. However, the introduction of large herbivores has been found to drive changes in the environment, potentially restoring or introducing novel ecological functions similar to pre-extinction Late Pleistocene conditions. This week’s researchers wanted to investigate what sort of role introduced mammals played in restoring ecological interactions by investigating their functional similarity with LP species.
Image Credit: US Fish and Wildlife Service Headquarters, CC BY 2.0, Image Cropped
Are polar bear habitat resource selection functions developed from 1985-1995 data still useful? (2019) Durner et. al, Ecology and Evolution, https://doi.org/10.1002/ece3.5401
Ecologists often attempt to predict where species are using the spread of the resources that the species depends upon. This is done because often it’s simply easier to monitor the resources than the species. Resource selection functions (RSFs) are a tool which use the likelihood of a resource being used to predict a species distribution. However, if the landscape the resource is found in changes drastically, a resource selection function may start to be less useful.
In the early 2000s, using data collected in the 80s and 90s, US scientists developed RSFs for polar bears, a species which has regrettably become the poster child for the survival of the Arctic ecosystem. Even back then, the bears’ preferred habitat was receding. Now, with human-driven climate change severely reducing sea ice and markedly altering the bears’ habitat, this week’s authors wanted to know how well those RSFs work nowadays.
Shelley Adamo was recently asked to testify before the Canadian senate as to whether or not lobsters felt pain (Image Credit: Marco Verch, CC BY 2.0, Image Cropped)
Dr. Shelley Adamo is a full professor at Dalhousie University in Halifax, Nova Scotia, Canada. An internationally recognized expert in the field of ecoimmunology and comparative psychoneuroimmunology, Dr. Adamo has an enormous amount of scientific experience in both the lab and field. In addition to her stellar career in academia, she has also brought her expertise and knowledge to the public, as she was recently asked to testify before a Canadian senate committee to discuss whether or not insects feel pain.
During Shelley’s recent visit to my university, I took the opportunity to sit down and talk to her about appearing before the senate, the concept of pain in invertebrates, and the plight of the insect world in general.