I am so excited and honored to introduce Joanie Mars as our new writer. When Joe and I started this little project about three years ago, we had no idea that it was going to grow into what it has. We now have over 8,800 followers on Facebook, we receive between 50-100 of your emails a week, and over 10,000 views a week on the blog. We just can’t keep up anymore! So we’re incredibly excited to introduce Joanie.
Joanie will be full time with us in August after she defends her thesis and moves to Texas.
Since it’s summer, and bug season is in full swing, we get a lot of neat observations in our inbox. I wanted to highlight one such observation in this week’s post, because it involves one of my favorite bugs:
Hello,
My name is Curt and I live in southeast Wisconsin. I saw these bees and thought it looked kinda odd. What exactly am I looking at?
I recently received this question when talking to one of the tourists at the Maquipucuna Ecolodge, where I work. I thought it was so interesting because we always hear about mathematical patterns – especially Fibonacci sequences found in leaves and shells – but what about the animal kingdom? So can you find any mathematical patterns in insects? Yes – but it’s not as apparent.
Sleeping Cuckoo Bee. Note the eyes. PC: Giles Gonthier (CC by 2.0)
Indian meal moths and grain weevils get into stored grain products and manage to complete entire life cycles without any access to moisture. How do they manage that?
I really like agricultural pests, stored product pests in particular. They have super cool biology, and they’re really important. Between the farm and the table, 10-15% of the harvest can be lost to bugs which live inside stored products. If that wasn’t bad enough, these bugs can break grains and mess with the humidity inside storage facilities. This damage introduces fungus, which can reduce the value of the product by as much as half its worth. This fungus can also make people very sick, so they’re important to both agriculture and medicine.
If you think about the environment these bugs live in, it’s very extreme. They live their entire lives without seeing a drop of water, all while evading hyper-intelligent animals which are constantly looking for new ways to kill them. There’s life in the driest deserts in the world, but these animals live in an indifferent environment. While harsh, these desert animals do not live in a place which is actively trying to kill them. You could argue that these bugs are the ultimate extremophiles.
So how do these guys get water in such a harsh place? Continue reading →
This is a really good question, for a number of reasons. There are sources which claim that male insects don’t contain sex hormones, but as far as I can tell, this goes back to a 1995 paper where a group of scientists weren’t able to replicate the results of a 1966 paper which explored this topic.
The literature is mostly agnostic on the topic of male sex hormones. Because female insects are the targets of most pest control efforts, more efforts have been put into controlling female reproduction than male reproduction. It’s still important, though, because the newer pest control tactics (like SIT) depend on manipulating male reproduction.
So even in graduate school, it kind of surprised me that this topic isn’t better studied.
We’ve talked about how insects produce male and female insects, and I’d refer you to theseposts for an idea of how that works. Instead of talking about how bugs make boys and girls, this post will be about how the boy and girl parts get booted up so they can begin making babies.
Awhile back, Nancy wrote a post about what happens when an insect turns into a cocoon. She also made a video about insect physiology that talks about what happens when an insect molts, and what happens when it turns into an adult.
There’s a lot of hormones involved, which are explained in Nancy’s video. Briefly, a hormone called Juvenile Hormone (JH) keeps the insect from turning into adult. Another hormone, 20-hydroxyecdysone (20-E), tells the insect to shed it’s skin. These hormones are conserved throughout insects; all insects use these hormones in the same way. This is a very important system, and is essential for understanding how insects turn into adults.
In order to discuss insect sex hormones, however, we need to forget all about what happens in the larval stages. Adult insects have hormone systems which are completely different from the larval insects. In essence, adult and larval insects are completely different animals.
I wanted to dedicate another post to some of my other concerns about the pro-DDT movement. When I read posts which advocate DDT reintroduction in the US, a small amount of attention is paid to issues like how public health programs are run or the importance of resistance to DDT.
A great place to explore how all these things interact is by exploring the situation in India. Not only are they the biggest DDT using nation in the world, India has also made some really wonderful strides in combating malaria, having slashed infections by more than half over a 13 year period. They’ve got some really good scientists working on this problem, who thankfully publish very often.
I’ve had a number of friends ask me to tackle the topic of possibly bringing back DDT. These requests go back months, and I’ve been hesitant to tackle the topic because of the politics surrounding this issue. I’ve also been hesitant, because if I tackle this topic, I want to do it right…which means this will probably be the longest article I’ve written on AaE to date. I hope that it will be the longest article, as well.
I want to tell a short personal story about Paul Offit. In 2014, I was diagnosed as an adult with autism. In some of my non-science social circles, my parents were blamed. Offit’s book, Autism’s False Prophets, helped me understand why this viewpoint existed and how to explain how the antivaccine movement hurts autistic people like myself. I admire him, but I also disagree with him on this point.
This comes on the heels of a pair of articles which had widespread press back in Feburary. One is by a blogger popular in the Skeptic community, SkepticalRaptor. The other is from one of my idols working in public health, a vaccine expert named Paul Offit. I initially wanted to tackle this in February, but ultimately decided to wait until Earth Day and World Malaria day to post these articles.
The story of the failed malaria eradication program is far more complicated than either Offit or Raptor let on. They leave out huge chunks of the story, and many of those chunks completely change the narrative. Specifically, they leave out any serious discussion of the role of insecticide and antimalarial drug resistance. They do not discuss the many administrative failures of the campaign, and neither of them seriously consider the role of economic development in malaria epidemiology.
Instead of laying out the standard DDT story most are familiar with, I’d like to discuss why the WHO’s Global Malaria Eradication Program failed, while the US campaign succeeded. Comparing and contrasting these stories is very productive, because it demonstrates why vector control is really hard.
