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Starting next week, this newsletter will be coming to you from Andrew Freedman, Axios' new Science Editor. I'll be moving into a new role here working on Axios Expert Voices but you'll still hear from me — I'll be writing science stories from time to time.
1 big thing: Revisiting limits on human embryo research
Scientists and ethicists are urging further debate over the current 14-day limit on research on human embryos, writes Eileen Drage O'Reilly.
Why it matters: Expanded research on early embryo development would provide untapped insight into how humans, and their diseases, develop, according to a group of scientists that spoke with Axios and at an event hosted by Rice University's Baker Institute Wednesday.
Context: An international agreement limits human embryo research to the first 14 days of development, which is when the embryo starts developing the primitive streak and its neural system.
- Of note: The U.S. has adopted the international agreement as guidelines rather than as policy, as many other countries have done. However, alongside this agreement, various U.S. states have even stricter policies, with some like North Dakota banning all research.
- Several speakers at the event said the 14-day limit was not really based on scientific thought but instead chosen in 1979 when In Vitro Fertilization (IVF) first started and people became worried about test tube babies. "None of it is actually scientific, I would argue," Rockefeller University's Ali Brivanlou said.
- To be sure: At the time, the limit didn't matter since scientists didn't have the technological know-how to be able to develop embryo cells for that length of time.
- However: Technology has advanced, and a couple years ago, Brivanlou's lab was able to develop embryos that successfully developed up to the 14-day mark and had to be frozen, a move he calls "one of the hardest things I've ever done."
What's happening now: Instead of human embryos, many researchers are using animal models such as mice, according to Kirstin R.W. Matthews, Baker Institute fellow in science and technology policy. The problem is that, while human and mice blastocysts look similar at 5 or 6 days, they look very different by day 14, she said.
- Rice University's Daniel Wagner, who spoke at the event, also noted they've been able to pinpoint how some birth defects may originate in animal models, but "we can't really validate these detailed findings in humans."
Go further: Read the whole story.
2. Measles returns to Europe and the Americas
Peter Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine, writes in an Expert Voices post today: Measles epidemics have surged in the past year, according to a new report from the European Centre for Disease Prevention and Control (ECDC) and one from the Pan American Health Organization.
The details: Between April 1, 2017, and March 30, 2018, there were more than 14,000 measles cases across Europe, led by Italy (4,448 cases), Romania (3,243), and Greece (2,400). The vast majority (84%) occurred among people who did not receive their measles vaccination, while only 4% of the cases were imported. In the latest dire development, more than 9,000 cases were reported in Ukraine in the first 13 weeks of 2018.
3. Axios stories worthy of your time
- Climate: Countries could save trillions of dollars by meeting temperature targets under the Paris Climate Agreement, per a new study.
- Biotechnology: With this experimental ingestible sensor, it's possible to detect internal bleeding using an Android app instead of an endoscopy.
- Transportation: A new forecast released this week shows that crossovers and SUVs may dominate the electric vehicle market, just as they have with gas-powered vehicles, per Axios' Steve LeVine.
4. Where lightning strikes the most
Every second on Earth, 100 lightning bolts strike the planet. That's about 8 million strikes per day, and 3 billion a year, on average. But as this map of nearly 9 billion lightning strikes shows, lightning is not evenly distributed around the world.
The bottom line: Each continent, except for the frozen reaches of Antarctica, has lightning hotspots — usually the parts that have clashing air masses or mountains. Spin the map and see where you're at the greatest risk of getting zapped.
5. What we're reading elsewhere
- Planet Nine: The discovery of an object with an odd orbit on the outskirts of the solar system offers new evidence in the search for a proposed planet beyond Neptune, from the Atlantic's Marina Koren.
- Deepfakes: Defining them is challenging, but it is important that we do as the use of AI to manipulate video and audio becomes more sophisticated, The Verge's James Vincent writes. Bonus: DARPA is launching a project this summer to try to spot such digital forgery, per MIT Tech Review's Will Knight.
- Kilauea eruption: From blue methane flames videotaped by the U.S. Geological Survey to this excellent USA Today explainer on "Laze," it's been a banner week of volcano news.
6. Something wondrous
A 130-million-year-old skull discovered in Utah is a rare fossil find that suggests primitive relatives of today's mammals lived throughout the supercontinent of Pangea, according to research published Wednesday in Nature.
What they found: Researchers unearthed a small, largely intact skull — about 7 cm long — from a new species, Cifelliodon wahkarmoosuch, that is part of a now extinct group of animals called the haramiyids. Their place on the tree of life is debated. Some scientists consider them members of the mammal family, while others view them as near relatives that share a common ancestor. Going with the former means mammals emerged 215 million years ago, the latter 30 million years later.
- C. wahkarmoosuch's highly specialized teeth and roots, primitive palate and about two-dozen other features indicate it is very closely related to mammals, but just outside the family, says Zhe-Xi Luo, a paleontologist at the University of Chicago and an author of the study.
- The complete skull is important for haramiyids as a whole because "it shows for the first time what the brain structure was like," says Luo.
Key insight: The teeth of C. wahkarmoosuch are very similar to ones in a haramiyid fossil found in Morocco. The authors argue those similarities geographically link North America and North Africa — contradicting the prevailing thought that Pangea was completely broken up by that time.
"Tying this to the breakup of Pangea is an interesting idea but cannot be proven at this point. There are other potential options but this is viable option,” says the University of Louisville's Guillermo Rougier, who was not involved in the research.
For Rougier, the skull highlights how little the southern continents are represented in the fossil record. “Most of what we know from early mammals comes from North America, Europe and Asia. We still have about half of the picture missing.”
Editor’s note: The date range in last week's Ancient Rome summary in the "What we're reading elsewhere" section was corrected to between 1100 B.C. and 800 A.D.