July 2024 science summary

Hello,

I've just got two science articles this month, but also wanted a plug a book I found really interesting: The Culture Code by Daniel Coyle. There's not a lot of brand new content - he draws heavily on concepts of psychological safety and vulnerability (see Amy Edmondson), learning from failure, how to give effective feedback, ways to generate candor and tough love, making space for feedback, etc.

The reason this one stuck w/ me is that he has pretty compelling real world examples of organizations and leaders that embody some of the recommendations. One of his suggestions was also new to me and really resonates: "resist the temptation to reflexively add value." I've thought before about 1) whether or not my review or input can make something better and how much, and 2) whether I'd add enough value for it to be worth my time. But he notes that 3) every time you weigh in on something, you're missing a chance to express trust in the author and build their confidence that they don't NEED your input for it to be good enough. I'm still grappling with how to put this into practice, but the book is a fast read and I recommend it.

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MAMMALS:
Greenspoon et. al 2023 is an attempt to estimate the biomass of all wild mammals on earth (combined), arriving at 60 Mt total: 20 Mt (million metric tons) on land (half from "even-hoofed" mammals, see FIg 2), and 40 Mt in oceans (23 Mt of which comes from baleen whales). But the kicker is that they estimate human biomass at 390 Mt, and livestock biomass at 630 Mt (420 Mt from cattle: which is more than all humans plus all wild land mammals). Fig 4 awkwardly tries to compare all mammal biomass on earth, showing how wild species have been squeezed. The wild mammal estimates mostly come from the IUCN red list which skews towards expert assessments of more threatened spp., and the numbers won't be "right" for several reasons (these estimates are hard, and the data are highly limiting). But it seems solid that humans and livestock substantially outweigh wild mammals.
There's a good critique of the paper (arguing that Greenspoon et al. underestimate biomass by a factor of 5.5) by Santini et al. here https://www.pnas.org/doi/10.1073/pnas.2308958121 and a reply from the Greenspoon authors pointing out why the methods used in the critique are also (differently) flawed: https://www.pnas.org/doi/10.1073/pnas.2316314121


PANTANAL / CATTLE RANCHING:
Junk and da Cunha 2012 argue that when ranchers clear trees and shrubs from grazing lands, that should not be equated with deforestation. They note that from the perspective of ranchers, all trees and shrubs within pastures (whether native or not) are "invasive species." It's unusual to use that language to describe the regeneration of trees in what used to be forest (as of ~250 years ago before cattle were introduced) but makes sense from the perspective of someone trying to keep land suitable for cattle (and they note the land was managed for thousands of years to promote other wild game species, making parts of the Pantanal a cultural landscape). Table 1 lists their recommended methods to clear some of the more common woody species. They also discuss how starting in the 1980s, money from a gold rush was used to drive higher-density cattle ranching using African grass species.


REFERENCES:
Greenspoon, L., Krieger, E., Sender, R., Rosenberg, Y., Bar-On, Y. M., Moran, U., Antman, T., Meiri, S., Roll, U., Noor, E., & Milo, R. (2023). The global biomass of wild mammals. Proceedings of the National Academy of Sciences, 120(10), 2017. https://doi.org/10.1073/pnas.2204892120

REPLY AND COUNTER-REPLY TO GREENSPOON:

• Santini, L., Berzaghi, F., & Benítez-López, A. (2024). Total population reports are ill-suited for global biomass estimation of wild animals. Proceedings of the National Academy of Sciences, 121(4), 1–3. https://doi.org/10.1073/pnas.2308958121   
• Greenspoon, L., Rosenberg, Y., Meiri, S., Roll, U., Noor, E., & Milo, R. (2024). Reply to Santini et al.: Total population reports are necessary for global biomass estimation of wild mammals. Proceedings of the National Academy of Sciences of the United States of America, 121(4), 1–2. https://doi.org/10.1073/pnas.2316314121

    
Junk, W. J., & Nunes da Cunha, C. (2012). Pasture clearing from invasive woody plants in the Pantanal: a tool for sustainable management or environmental destruction? Wetlands Ecology and Management, 20(2), 111–122. https://doi.org/10.1007/s11273-011-9246-y



Sincerely,
 
Jon
 
p.s. This is a baby rabbit nibbling a weed in my garden. We had a nest of even tinier ones born more recently, but this guy was the cutest of them all.