A foreigner researching in Brazil

By Sabine Schultes

While writing this post, I'm at my work desk in the Munich Biology Faculty. From the window, I see green fields; the only salt water in a 600km (~370 mi) radius is a mere 20L (~5 gal) of artificial seawater in the laboratory, in a bucket containing copepods of the species Acartia tonsa. That's what is connecting me with my great passion, the study of biological oceanography.

Copepods are minuscule crustaceans, around 1 millimeter (~0.04 in) in length. With the naked eye, they look like jumping little dust particles in water. They live in all water ecosystems including lakes, rivers, underground water, and oceans. Their numbers seemingly rival the stars in the universe, and as they are so numerous, they have an important role in ocean ecology. They consume the biomass created by microalgae through sun energy – in a process called primary production – and transfer it to fish, as fish like to eat copepods. (Learn more about it here)

Copepods

I have worked with copepods from the temperate waters of the North Atlantic, from the cold Antarctic ocean, and in 2007 I went to work as a post-doctoral researcher in the Oceanographic Institute of USP (University of São Paulo) to get to know the tropical copepods. What a joy! …and, at the same time, what an adventure to live in São Paulo, in a country 12000 km away from Germany. I jumped in without thinking twice and, when in a taxi at “Marginal Tietê,” between Guarulhos and the University City, I suddenly realized that I was far away from home. It is in these transitional moments, moving from one world to another, that all details are fixed in our memories. I was warmly welcomed by the “Paulistanos” (those who live in São Paulo) and, although Brazil is known for its beaches, samba and caipirinha, I had the opportunity to work with high-end technology in my research field.

I was in charge of two sophisticated instruments for my copepod analysis. My job was to establish measurements and calibration protocols. There was no bias or concern that “a woman does not understand technology.” Every day my learning experience was huge: living in a big city in a tropical country, Portuguese, image analysis techniques, electronic data exchange. Also huge was the help I received from science colleagues from Brazil, Canada and France. In only a short while, it was possible to christen the equipment in the Oceanography base at Ubatuba. For a marine science researcher, that was a dream coming true.

The famous LOPC is a particle profiler, that can detect, count and measure plankton with high spatial resolution. By Catarina Marcolin.

Another dream was coming true with the expedition of the project PROABROLHOS: to study with said equipment the zooplanktonic (copepods and other tiny animals) distribution on the Abrolhos Bank. There's a bunch of fish there, and remember that fish like to eat copepods! In this project, researchers from various universities of Brazil and the world joined forces in order to enhance the understanding on how this ecosystem operates, in order to protect the great biodiversity of Abrolhos and it's value to society (http://laps.io.usp.br/index.php/90-portugues/laps/projetos/155-proabrolhos).

To spend one month on board of the old oceanographic ship Prof. Besnard was quite the adventure (it has finally been retired – now the oceanographic institute has a new ship), but all worked out. Our results were published in the following years (2009 to 2013), but I decided to go back to Europe before that. How come?! Wasn't that a dream come true??

Yeah, well, looking back, I can sense I lacked some faith. But also, maybe I needed to be around my own people, culture, and family to get the faith to keep on studying the oceans of the world. Unfortunately, life in science is filled with uncertainties and short work contracts (1 year). At the same time, scientific realizations take years. To write a project, get funding, execute it, analyze the results, and communicate that new knowledge all happens in 5-10 years’ time.

Back from Brazil, it took me another 4 years of coming and going between France, Brazil (I fell in love), and Germany for me to finally get a position as a teacher in the Faculty of Biology of Munich in 2012, when I was 40. I live near my parents' house, and I am teaching zoology, ecology, and scientific initiation to undergrad and grad students. For the first time, I know where I will work, live, and study the ocean, until at least 2020, when the future may take me down another path.

I had few preconceived ideas before coming to Brazil. I like living in other countries. I usually try, at first, to observe and go with the flow. I discovered the “Brazilian way” of doing things, the São Paulo coldness, and I learned how to dance forró. I thought – still do – that all of the people around me were very dedicated to work, friends and family. The most important thing I learned in Brazil? That sometimes things may take a while, but all works out in the end!

In Rio Grande, RS, Brazil

About Sabine:

Sabine Schultes likes to see herself as biologist and oceanographer. She studied biology and hydrobiology in the Hamburg faculty, defended her masters in oceanography at the Université du Québec Rimouski, Canada and her doctorate at Alfred-Wegener-Institut, Bremerhaven. After some post-doctoral contracts in France and Brazil, she is now a teacher at the Munich Faculty (LMU), teaching zoology and ecology. She says that her parents taught her how to look for new paths and to socialize with people and cultures around the world. She is convinced that today, more than ever, we need to take care of our oceans.  

Sabine has also published:
http://chatwithneptune.blogspot.com.br/2016/09/sun-protection-cosmetics-good-for-you.html

Finding self-confidence as a woman in science

By Deborah Apgaua

In 2016 this year I received an international award that changed my life and perspectives about many aspects on science. This award was granted by the Schlumberger Foundation under their Faculty of the Future program, and is intended for women from developing countries to conduct research in the fields of science, technology, engineering and math (STEM). The program aims to form a transformative network where men and women have similar opportunities in the job market.

Illustrated by Caia Colla

To be a woman in science is still a challenge, especially in a developing country like Brazil, where the biggest portion of professors in STEM are men, and where gender imbalance is evident in leading positions. According to a post already published in this blog (o sexo realmente importa?), it may help to reverse this scenario by accepting that this gender imbalance exists, but this has still not happened. Even more importantly, an increase in self-confidence in women could help to break this barrier towards a greater female participation in STEM.

The possibility of pursuing post-doctoral research overseas is of course an important component of the satisfaction that I feel after winning the award. To be part of the Faculty for the Future community that searches for new directions for science enhanced my self-confidence to develop research and to become a role model to inspire other women to follow a similar path. Therefore, way before I started my research, I already felt a big change in the way I expressed my ideas and guide students in their work.

When I decided to try this program, I had to remember and mentally organize my entire academic carrier from my undergrad to my doctorate. I had to search for value in each experience and think about how these experiences can help me inspire other women. Thus, I discovered a new force that was inside me, something that I did not know. Before submitting the proposal for my research, I reread it and felt fulfilled, regardless of the application results. I asked myself how many women could feel this contentment if they remembered each step of their journey and add value to their work.

For example, I realized that I have more teaching experience than I was aware. During my undergrad, I developed research in traditional communities where I participated in giving short courses and presenting user-end research outcomes.  Besides this, during my postgrad I had acquired experience through teaching placements, and this counts as teaching experience even if it was with the assistance of my supervisor. While doing part of my doctorate studies overseas, I kept in touch with my work mates back in Brazil, and helped in reviewing academic texts. Therefore, I could see the relevance of all those moments when I had to convince the Schlumberger Foundation that I am a candidate that deserves the award.

To believe in this reality without diminishing myself, but on the contrary, finding merit in my academic choices, I did not worry about what I could have done but I didn’t. When I was interviewed in English with the intention to confirm what I wrote, I did not present myself as a “serious and baddie” person trying to show a masculine stereotype to express power. On the contrary, I was friendly and feminine finding confidence being myself.

When I received the positive results on my proposal, the “insecure girl that could not express her scientific ideas because she did not believe it was relevant” disappeared. As I resonate with the philosophy of the Faculty for the Future program, I decided to accept the mission to engage and encourage more women in science. I have chosen to embrace the strong woman that was sleeping inside me and see myself as a scientist that searches for even more experiences knowing that I still have a lot to learn.

Since that moment, with my self-confidence renewed, I have talked to women in my university and from other institutions and I see their countenance changing as I point to the possibility of a simple path to achieve their goals. The change is inside us, because many times we boycott ourselves, with insecurity and low self-esteem. Focus and self-confidence are the key ingredients for our transformation.

Talking with female post-grad students in my department, I noticed that some of them are afraid to become a “shadow” of their male counterparts.  Perhaps this is a result of a predominantly male work environment where only three out of 31 professors are women. However, this is a fear that freezes, and it is only by acting on our academic goals that we can be free from this self-perceived subordination. So when we overcome the insecurity and fear of being overshadowed by men in science, we are on our paths of knowledge that will bring us to academic success.

Overcoming our insecurities and fears is also facilitated when we understand that we do not do science alone and that working together with others is essential. This way, we can transform competition to collaboration, and not have to feel that we are alone in our academic endeavors at every step of our work. Scientific knowledge is an ever-expanding thing.  Men or women alike, trusting that science moves forward by our combined efforts reduces our ego and dispels the perceived ideal that we have to know everything to be able to do good science.

Relevant Links:

https://www.researchgate.net/profile/Deborah_Apgaua

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0130799

http://onlinelibrary.wiley.com/doi/10.1111/1365-2435.12787/abstract

http://www.ufla.br/ascom/2016/09/06/estudante-da-ufla-e-contemplada-com-premio-internacional/

https://www.youtube.com/watch?v=deUQFTSX0EY

About Deborah:

I am a doctor in forest ecology, and I have a deep love for the world’s tropical forests. I have graduated in biology during which I studied ethnobiology. During my masters and PhD I worked with forest ecology to be in contact with Brazilian forests. During my Ph.D however, I ended up going to Australia where I developed a project with plant functional traits in rainforest plants. More recently, I am preparing to go back to Australia again to pursue a post-doc, supported by an award that I received for women in science. I aim to understand how plants cope with drought through their traits and bring this knowledge to Brazil. I hope to inspire other women to pursue the academic career.

Sun protection cosmetics – good for you, bad for the aquatic environment?

By Sabine Schultes

Most people who like the sea and the shore also enjoy a sunny day at the beach, playing in the water when the weather is warm. Luckily, the education campaigns for skin cancer protection have made us all aware of the importance of protecting ourselves from harmful ultraviolet (UV) radiation which is a part of natural sunlight. UV light is at the lower end of the light spectrum and is divided into UVA, UVB and UVC. The highly energetic UVC is absorbed by our atmosphere, but UVA and UVB reach the surface.

Wavelength spectrum of natural sunlight.

So, we all adopted the habit to regularly apply cosmetic sunscreens before sunbathing, but we are typically not as attentive when it is time to take a dip in the lake or ocean. Probably, you are just like me and are so anxious to cool off, that you rush over the hot sand and to take a wonderfully refreshing dive head first into the waves.

© worldartsme.com/

UV radiation is not only a problem for us, but for all living beings, especially if they are without protective pigmentation, feathers, fur, or scales. Single-celled organisms have it even harder, so much so that one way to kill bacteria to make a sterile environment is to expose the lab bench to a couple of minutes of UV radiation. Sunburn for a single cell is lethal!

Plankton are, in most cases, single celled or transparent, so they are very sensitive to UV light. Luckily, ocean and lake water progressively absorbs the incident sunlight. Depending on how clear the water is, UV light only reaches a few meters below the surface. Planktonic organisms have nevertheless evolved repair mechanisms to cope with the constantly occurring DNA damage.

Alternatively, plankton can avoid UV radiation by migrating to water depths with no or little UV radiation. This strategy has been adopted by the zooplankton such as some copepods . Other copepods that live in very clear alpine lakes or in the surface layer of the tropical ocean are pigmented, often orange or even blue! Instead of getting a suntan - when our skin cells produce melanin - the zooplankton simply accumulates the pigments from their algal food. One example are the beautiful blue copepods from the genus Anomalocera, in the family of the Pontellidae.

Now, what happens if you and I take our dive into the waves and the sunscreen we have applied to our skin is washed off, into the sea? Yes, large parts are washed off, even if you use waterproof lotion. Looking through the scientific literature makes it clear: sunscreen cosmetics are a source of pollution with growing concern. Waters of popular beaches all show high concentrations of the organic molecules used as chemical UV filters in sun protection creams. Very low concentrations (10µg/L) are sufficient to promote coral bleaching. The chemicals persist in the aquatic environment and accumulate in mussels, fish and dolphins. Lakes and rivers are also subject to this type of contamination.

This is why I have decided to do at least two things:

1. Before taking a swim I will try to get rid of most of the cream on my skin. Many modern beach facilities have showers connected to a wastewater system. So why not have a quick wash before you dive? If showering is not an option, I bring baby wipes and rub off the excess.
2. I started to do my own research into the question. I am interested in learning how plankton growth and diversity is affected by sublethal concentrations of sunscreen. Is the pelagic food web disturbed? Are there alternative cosmetics available with potentially less harmful effects for the aquatic environment?

Sunscreen cosmetics are complex mixtures of organic UV-filters (e.g. oxybenzone, octocrylene, …), oils, perfumes, stabilizers and often nanoparticles. Our experiments also try to find out, which of the components are particularly harmful, and if sunscreen cosmetics that are solely based on natural oils may be a better option for the aquatic environment. I will tell more about this in my next post - so wait and see!

Preliminary results show that plankton growth can either be enhanced or reduced when the water is polluted with conventional sunscreen, depending on the concentration we add and whether the water comes from an oligotrophic or eutrophic environment. The community composition of the phytoplankton is modified because some algal groups are more sensitive to sunscreen pollution than others. The use of sunscreen may even be one of the causes of cyanobacterial blooms in recreational lakes leading to skin irritation in summer swimmers.

We need recreation, and we need to protect ourselves from UV radiation to prevent skin cancer. How can we fulfill the needs of human society without totally spoiling our environment?  This question is exemplary for many issues in nature conservation!  So, I am passing this question on to others and will make an opinion poll at the beach...

Beach life in Ubatuba, Brazil (left). Beach life in Munich, Germany (right).

    

Further reading:

Balmer, M., Buser, H.R., Müller, M.D., Poigner, T. 2005. Occurrence of some organic UV

filters in wastewater, in surface waters, and in fish from Swiss lakes. Environ. Sci. Technol. 39: 953-962

Cunha, C.,  Fernandes, J.O.,  Vallecillos., L.,  Cano-Sancho, G., Domingo, J.L., et al. 2015. Co-occurrence of musk fragrances and UV-filters in seafood and macroalgae collected in European hotspots. Environ. Res.143: 65–71

Danovaro, R., Bongiorni, L., Corinaldesi, C., Giovannelli, D., Damiani, E., et al. 2008. Sunscreens cause coral bleaching by promoting viral infections. Environ. Health Perspect. 116:441–447

Gago-Ferrero, P., Alonso, M. B., Bertozzi, C. P., Marigo, J., Barbosa, L., et al. 2013. First determination of UV filters in marine mammals. Octocrylene levels in Franciscana Dolphins. Environ. Sci. Technol. 47: 5619−5625

Sánchez Rodríguez, A., Rodrigo Sanz, M., Betancort Rodríguez, J.R. 2015. Occurrence of eight UV filters in beaches of Gran Canaria (Canary Islands). An approach to environmental risk assessment. Chemosphere 131: 85–90

Tovar-Sánchez, A., Sánchez-Quiles, D., Basterretxea, G., Benedé, J.L., Chisvert, A., et al. 2013 Sunscreen products as emerging pollutants to coastal waters. PLoS ONE 8(6): e65451.

About Sabine:


With the goal to become a marine biologist, I studied biology and hydrobiology at Hamburg University and then earned a Master’s degree in oceanography from Université du Québec à Rimouski, in Canada. My doctoral studies in biological oceanography at the Alfred Wegener Institute in Bremerhaven were followed by various post-doc projects in Brest, France and Sao Paulo, Brazil. Since 2012, I teach ecology and zoology at LMU Munich. Growing up, my parents gave me the incentive to search new ways and to relate with people and cultures around the world. I am convinced that today, more than ever, we need to take good care of our Oceans.

A new home for Nemo

By Cathrine Boerseth

People don't like having their homes destroyed and neither do animals; bears don’t like it, birds don't like it, fish certainly don't like it and neither do the tiniest planktonic animals that people often forget even exists. Some of these tiny animals are meroplanktonic, which means they only float around in the early stages of their lives, to grow up as adults they need somewhere to settle down, a nice home with a good foundation; for many organisms that means a hard surface like rocks or a coral reef. 

Sadly, in the waters of northern Paraná state, many of these nice hard (and already rare) surfaces were destroyed by destructive fishing methods like trawling. The meroplanktonic larvae were still floating around in the water, but there were few places for them to settle down. In the biological world one thing always affects another and so did the lack of appropriate habitat in our case; fish eat the organisms living on and around rocky reefs and so the lack of hard bottom substrates meant a lack of food for the fish, and so the populations declined.

But what if we made new homes for these animals and what if those homes were so sturdy and strong that trawlers wouldn't be able to break them? Well, that’s exactly what researchers did between 1997 and 2013 when they deployed a number of artificial reefs along the Paraná coast. But what exactly is an artificial reef? An artificial reef can be made out of rocks, concrete blocks or even sunken ships. They are man-made structures, preferably with different holes and crevasses, placed under water to provide shelter for marine organisms. Bacteria and algae are usually the first organisms to arrive, meroplanktonic larvae settle and grow up to be anything from anemones to crabs; all of these animals attract fish looking for food and they in turn attract larger fish and other predators.  After a while, the ecosystem on the artificial reef grows to become a place with both food and shelter for all kinds of marine organisms.

However, even after the artificial reefs were in place, many questions were still unanswered: would meroplanktonic organisms come to settle? Would they attract fish? Would those fishes reproduce? Would the ecosystem of the artificial reefs be anything like a natural rocky reef? The answer to the two first questions was discovered to be a big YES, but what about the other questions? That's what I wanted to find out! Exiting stuff, now what?

To answer those questions, we decided to look at fish larvae and fish eggs. To capture them we used a net attached to an underwater scooter (so cool, I know), and a light-trap. With the scooter and light-trap we were able to capture larvae very close to the artificial reef; the net captured eggs and the smallest fish larvae while the trap attracted larger larvae. We also sampled at a distance from the artificial reef (would the abundance of larvae and eggs be different there?) and at a natural rocky reef habitat nearby (the beautiful archipelago of Currais). We collected as many samples as the weather and waves allowed between the July of 2014 and April of 2016.

The samples were collected using a light-trap (left) and a net attached to an underwater scooter (right).

Currais archipelago on the Paraná coast.

So what did the data show?  

The number of fish larvae and fish eggs was in fact higher on the artificial reef compared to samples taken at a distance from the reef. Furthermore, the fact that the samples contained eggs and very small newly hatched larval fish means that fish are either reproducing on the reefs or close by. Additionally, many of the fish larvae collected on the artificial reefs belonged to species that are known to live on rocky reef habitats; most of the other species found were pelagic, which means they live in the open water. What does it all mean? Well, it means that the artificial reef is beginning to act like a natural reef (great!), but it still has a way to go. Fish are still more abundant on the natural reef and many of the fishes on the artificial reef are more like visitors, like the pelagic species. They are all welcome of course! The artificial reef provides food and shelter; many of the visitors attracted by delicious food become food themselves, but that's ok, it's all part of the food network. 

It may sound like artificial reefs are the solution to all of our problems and you may want to stand up with your hands in the air shouting: let's put artificial reefs in all the seas in all the world! Then everything will be great again, right? That would be amazing, but unfortunately, as with most things in life, it's just not that simple. There are many factors to consider because deploying an artificial reef is in itself a human intervention in nature and could cause more harm than good, careful research in each individual case is essential!

What can we learn from all this? Nature finds a way. Humans are destructive; in order to get our way and build our houses, we destroy houses of so many other animals. Fortunately, given time, many ecosystems are resilient enough to come back to life. Artificial reefs may not be the answer to all our problems, but on the coast of Paraná it appears that a tiny piece of a suffering ecosystem may actually be getting back on its feet. 

About Cathrine:

Biologist and currently preparing to defend my masters’ dissertation in the field of biological oceanography at the University São Paulo. As a true Norwegian I fell in love with the ocean scuba diving in the freezing waters of the north. I have been living in Brazil for four years now and I can't wait to discover where life will take me in the future. What I know with certainty is that I want to work and live close to nature, that being in the beautiful tropics of Brazil or in the wonderful Arctic of Norway (or somewhere in between).   

How do tiny animals in the ocean influence atmospheric carbon dioxide?

By Emma Cavan 

The important role  small (< 5 mm) plants and animals play in the ocean is widely unknown to the public, as the media prefers to broadcast ‘cuddly,’ charismatic  animals such as dolphins and whales. However, the plankton are very important. Plankton are defined as organisms (both plants and animals) that cannot swim against the currents and range from microscopic algae to huge jellyfish. 

My research is on the biological carbon pump, described by Yonara Garcia in a previous post ‘Ocean fertilization and climate change’ (May, 2016).  The biological carbon pump describes how phytoplankton (plants) and zooplankton (animals) drawdown carbon dioxide from the atmosphere to the deep oceans.  I am most interested in how this biology transports organic carbon (as particles) through the upper ocean (top 500 m).

Image of crustaceous zooplankton 
about 0.5 mm in length. Photo by Emma Cavan.

Zooplankton range from tiny crustaceans (shrimp-like animals) to much larger salps and jellyfish. Here I am just going to concentrate on the crustaceans. One commonly known crustaceous zooplankton is krill, which are large (2-5 mm) for their group and are often found in abundance in the Southern Ocean. They are the food prey for large baleen whales such as humpback whales. Zooplankton change how much organic carbon (originally photosynthesised by phytoplankton in the surface ocean) reaches the deep sea as they:
1. Respire inorganic carbon; 
2. Ingest the carbon and release some as packaged faecal pellets;
3. Break particles into smaller pieces.

To further complicate the process zooplankton can migrate 100s of metres per day vertically, so they may eat at the surface at night, then at dawn sink deeper in the ocean and release faecal pellets there, increasing the amount of carbon reaching the deep ocean and away from the atmosphere. Hence zooplankton are particularly hard to accurately represent in biogeochemical models! I have been to sea in the Southern Ocean and the Equatorial Pacific to find out how zooplankton affect the transfer of organic carbon to the deep ocean.

Southern Ocean

At sea in the Southern Ocean, Elephant Island where
Ernest Shackleton landed is in the background.

Working in the Southern Ocean is an amazing experience. It has to be one of the most beautiful places on Earth. We were surrounded by so many penguins every day! Back to the science though… As I said, the Southern Ocean has a high number of crustaceous zooplankton such as krill and copepods. They can thrive in the cool waters around Antarctica but are very patchy (not evenly spread throughout).

Faecal pellet, 0.3 mm in length.
Photo by Emma Cavan.

Here I collected sinking organic particles (full of carbon) and they turned out to be mostly zooplankton faecal pellets (as opposed to detrital phytoplankton). This suggests that most of the organic carbon reached the seafloor from zooplankton grazing on the phytoplankton and releasing faecal pellets. The number of zooplankton present was shown to actually affect how many particles sunk out of the surface ocean. Further, whether zooplankton were feeding on fresh phytoplankton (brown faecal pellets) or detritus or their own faeces (white faecal pellets – and yes, they eat their own poo!) affected how efficiently organic carbon reached the deep ocean! So these little critters were playing an important role in transferring organic carbon from the surface to the deep ocean here.

Equatorial Pacific
Working here was very different from the Southern Ocean; it was extremely hot, and I saw barely any clouds the entire cruise. We were working off the Pacific coast of Guatemala, and while there was a lot less sea life here, I did see a lot of turtles and even a Thresher shark! 

                  RRS James Cook at port in Panama before the cruise. Photo by Emma Cavan.

Compared to the Southern Ocean, the Equatorial Pacific is very stable with little change in seasons. Between 100-1000 m in this area of the ocean, oxygen concentrations plummet, so organisms are extremely oxygen starved at these depths. Oxygen minimum zones (OMZs) are common around the globe, particularly near coasts such as off of Peru and the west coast of Africa. Many studies have shown that in OMZs, a much higher proportion of organic carbon reaches the deep ocean compared to rest of the world. But the reason for this is still unknown and so I went to sea to find out.

There are two main reasons why organic carbon doesn’t reach the deep ocean:
    1. It is consumed and respired by zooplankton;
    2. Or it is hydrolysed by bacteria.

Micro-respiration system used to measure
bacterial respiration on particles. An oxygen sensor
(blue) is inserted into the small vials which
contain particles to measure oxygen concentrations
over a few hours. Photo by Emma Cavan.

So I wanted to test if bacterial ‘remineralisation’ (process of converting organic carbon back to inorganic carbon, like carbon dioxide) is reduced in OMZs because bacterial metabolism is limited by the low oxygen concentrations. To do this, I measured the respiration of microbes on particles.What this showed was that actually microbes are very well adapted to live in the low oxygen conditions and were responsible for most of the organic carbon degradation! 


This meant that likely a reduction in zooplankton respiration and processing of particles in the OMZ must be why such a high proportion of the organic carbon reaches the deep ocean. This seems like a reasonable hypothesis as studies have shown zooplankton abundance is low in OMZs and their metabolism is greatly reduced. The life cycle of bacteria is much shorter than zooplankton so they can adapt much faster to challenging conditions.  So in the Equatorial Pacific, the absence of zooplankton means more carbon reaches the deep ocean and cannot be exchanged with the atmosphere.

To summarise, zooplankton have a complicated relationship with carbon in the ocean. Both their presence and absence can increase the amount of carbon in the deep ocean, it just depends on the oceanic ecosystem they are part of. This is why it is complicated to model their effect on the carbon cycle and more work is needed to constrain it better. But we should remember tiny animals do indeed influence how much carbon dioxide is in the atmosphere. Who would have thought it?!

About Emma: 
Emma is a marine biologist turned biological oceanographer (which basically means marine biologist of small organisms!). She grew up on the south coast of England and attended the National Oceanography Centre at the University of Southampton, UK, for both her undergraduate and PhD degrees. She has just finished her PhD and is hoping to stay in academia and continue researching. Emma is also very interested in connecting science and policy and spent 3 months working at the Royal Society in London in their science policy centre. Aside from science Emma likes to travel as much as possible and has been able to do so both for pleasure and with work. She also loves kayaking, camping, reading, napping and socialising.
Follow Emma on twitter @emma_cavan or visit http://emmacavan.wix.com/emmacavan