Subirdia

Welcome to Subirdia: Sharing Our Neighborhoods with Wrens, Robins, Woodpeckers, and Other Wildlife

NPR reviews an upcoming book called Subirdia, which says that in temperate areas, there are more bird species in the suburbs than in cities or even forests:

So what have suburbs got that forests don’t? Suburbs, he says, offer a wide range of artificially designed garden habitats, providing a smorgasbord of nuts, fruits, seeds, insects and ponds, in dense concentrations. Because they are rich with different kinds of bird food, suburbs are rich with different kinds of birds…

But let’s not get crazy about this: suburbs are not the birdiest zones on earth. Any patch of tropical forest, with its dazzling populations of plant and animal life, will trump a garden-rich suburb. But if you are comparing suburban bird diversity to temperate wild spaces — say the Cascades, the Smokies or the Adirondacks — the suburbs, shockingly, win.

So maybe our goal in denser cities should be to create a landscape with more of this variety of garden habitats. That is doable, and a much more attainable goal than trying to create forest-like habitat in cities. There are some shy species that won’t come to the city, but the city can be pleasant for a wide variety of species, even humans, if we work at it.

please remind me, what are patents for again?

Okay, maybe so-called intellectual property rights encourage innovation in some industries sometimes. But the evidence shows that they sometimes do the exact opposite, especially if taken to the extreme. This is the abstract of a working paper from the National Bureau of Economic Research:

Cumulative innovation is central to economic growth. Do patent rights facilitate or impede follow-on innovation? We study the causal effect of removing patent rights by court invalidation on subsequent research related to the focal patent, as measured by later citations. We exploit random allocation of judges at the U.S. Court of Appeals for the Federal Circuit to control for endogeneity of patent invalidation. Patent invalidation leads to a 50 percent increase in citations to the focal patent, on average, but the impact is heterogeneous and depends on characteristics of the bargaining environment. Patent rights block downstream innovation in computers, electronics and medical instruments, but not in drugs, chemicals or mechanical technologies. Moreover, the effect is entirely driven by invalidation of patents owned by large patentees that triggers more follow-on innovation by small firms.

microbial life on Mars

Here is some more evidence from the journal Geology that microbial life may exist or once have existed on Mars.

Depletion of phosphorus, vesicular structure, and replacive gypsic horizons of these Martian paleosols are features of habitable microbial earth soils on Earth, and encourage further search for definitive evidence of early life on Mars.

I’m interested in the question of whether life on Earth is truly alone in the universe. If we find just one bacterial cell on another planet, and as long as we don’t think that cell came from Earth or is an ancestor of life on Earth, the question will have been answered. If we can find life just one other place, then it will be likely that there is life all over the place.

the zombie cat virus

If there’s one thing I don’t put a whole lot of stock in, it’s scientific and medical information provided by random websites. Like this one, Corante, which claims that toxoplasma, a virus that incubates in cats, affects rats’ brains so that they are less afraid of cats. Then it goes on to suggest that half of all people are infected with this virus, and that it has unknown, subtle but possibly harmful effects on people. It just makes me think about how little we really know about most of the vast community of microorganisms inhabiting our bodies. The scariest thing would be something that is harmful, but has a long incubation period so it can infect a large fraction of the population before we are even aware of it.

connectivity and corridors

From Conservation Biology, here’s an article on connectivity and movement corridor models for wildlife:

Habitat corridors are important tools for maintaining connectivity in increasingly fragmented landscapes, but generally they have been considered in single-species approaches. Corridors intended to facilitate the movement of multiple species could increase persistence of entire communities, but at the likely cost of being less efficient for any given species than a corridor intended specifically for that species. There have been few tests of the trade-offs between single- and multispecies corridor approaches. We assessed single-species and multispecies habitat corridors for 5 threatened mammal species in tropical forests of Borneo. We generated maps of the cost of movement across the landscape for each species based on the species’ local abundance as estimated through hierarchical modeling of camera-trap data with biophysical and anthropogenic covariates. Elevation influenced local abundance of banded civets (Hemigalus derbyanus) and sun bears (Helarctos malayanus). Increased road density was associated with lower local abundance of Sunda clouded leopards (Neofelis diardi) and higher local abundance of sambar deer (Rusa unicolor). Pig-tailed macaque (Macaca nemestrina) local abundance was lower in recently logged areas. An all-species-combined connectivity scenario with least-cost paths and 1 km buffers generated total movement costs that were 27% and 23% higher for banded civets and clouded leopards, respectively, than the connectivity scenarios for those species individually. A carnivore multispecies connectivity scenario, however, increased movement cost by 2% for banded civets and clouded leopards. Likewise, an herbivore multispecies scenario provided more effective connectivity than the all-species-combined scenario for sambar and macaques. We suggest that multispecies habitat connectivity plans be tailored to groups of ecologically similar, disturbance-sensitive species to maximize their effectiveness.

Ebola

The Ebola situation makes for some scary headlines. From the CDC, the number of cases as I write this (July 31) in Guinea, Liberia, and Sierra Leone is 1,322 of which 728 (55%) have died.

Ebola is a disease with no known cure which incubates in bats. To put these numbers in perspective, Wikipedia says that 8,231 people in Haiti have died of cholera since 2010, a disease we know the exact cause of and exactly how to prevent (clean drinking water) and treat (staying hydrated with clean drinking water).

R and NetLogo

I had never heard of Netlogo, which is a programming language for simulating and teaching agent based models. Agent-based modeling is important because it might be the key to real quantitative simulation in economics and the social sciences. You can keep drilling down into the links in this post from R-bloggers until you either run out of time or find out everything you want to know about it.

Lords of Finance

Lords of Finance: The Bankers Who Broke the World

This book was kind of a hard read, but I’m glad I read it. My favorite part of the book was the last five pages, particularly these quotes explaining just how bad the Depression really was.

Anyone who writes or thinks about the Great Depression cannot avoid the question: Could it happen again? First it is important to remember the scale of the economic meltdown that occurred in 1929 to 1933. During a three-year period, real GDP in the major economies fell by over 25 percent, a quarter of the adult male population was thrown out of work, commodity prices fell in half, consumer prices declined by 30 percent, wages were cut by a third. Bank credit in the United States shrank by 40 percent and in many countries the whole banking system collapsed. Almost every major sovereign debtor among developing countries and in Central and Eastern Europe defaulted, including Germany, the third largest economy in the world. The economic turmoil created hardships in every corner of the globe, from the prairies of Canada to the teeming cities of Asia, from the industrial heartland of America to the smallest village in India. No other period of peace time economic turmoil since has even come close to approaching the depth and breadth of that cataclysm…

[The Great Depression was] a crisis equivalent in scope to the combined effects and more of the 1994 Mexican peso crises, the 1997-98 Asian and Russian crises, the 2000 collapse in the stock market bubble, and the 2007/8 world financial crisis, all cascading upon one and other in a single concentrated two-year period. The world has been saved in part from anything approaching the Great Depression because the crises that have buffeted the world economy over the past decade [writing in 2009] have conveniently struck one by one, with decent intervals in between.